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Gerrymanders, Part 1: Busting the both-sides-do-it myth

December 30th, 2012, 12:29pm by Sam Wang

Here’s a video explainer on how to detect partisan gerrymandering:

To learn more, see Help us with a donation!

Update, September 2018: I have expanded the analysis below to include three independent tests to detect gerrymandering – you can read more about them in the Stanford Law Review. The ideas are also described in the New York Times [February 2013] [December 2015] [August 2017]. Over at Election Law Blog and the American Prospect, we show that the trickle of extreme gerrymanders became a flood only after 2000.

A common objection to this analysis is that population density can account for asymmetry in outcomes. This belief is outdated. As of today, partisan gerrymandering effects have a larger effect on representation than population density.

Left: Eric Carle's caterpillar. Right: NC 12th DistrictThe Washington Post Second Annual Wonky Awards are out. Wow, there I am for Best Election Modeler. Thank you!

(Mental note: If I ever meet the Worst Modeler recipient, Dick Morris, remember to avoid shaking hands. The whole particle-antiparticle thing. We’d annihilate or get stuck together. Either outcome is bad.)


As current negotiations over the [fiscal cliff] / [austerity bomb] make clear, rank-and-file Republicans in the House of Representatives are not receptive to the policy implications  of November’s election. As correctly pointed out by Nate Silver,  members of Congress are increasingly insulated by the increasing polarization of their districts. Ever-larger victory margins reflect ever-safer re-election races.

However, Silver has also restated a common belief. He states that partisan gerrymandering is a symmetric problem, i.e. both Democrats and Republicans do it. Although both sides are potentially motivated, only one side has taken redistricting to extremes. Recent changes in partisan gerrymandering constitute one of the major crises facing our system of government (link to Mann/Ornstein book, a fellow Wonky winner).

Today I give an analysis that pinpoints some exceptional – and asymmetric – aspects of this year’s Congressional redistricting. I base this on criteria I have developed for identifying when a political party has been disenfranchised in a particular state. I conclude that the antidemocratic balance of power in the incoming Congress is driven by just a handful of states.

In this and coming posts I will address the following topics:

  • Part 1: Developing a “tell” for partisan gerrymandering, and evidence for partisan asymmetry.
  • Part 2: An estimate of how many people have been disenfranchised.
  • Part 2/3: Steps that would re-enfranchise voters by 2020 or sooner.

Let’s start with some simple but telling examples. A minimum condition for a “representative” outcome is that within a Congressional delegation, the party receiving more votes should end up with more Congressional seats.

As an example, consider Colorado. There, 51.4% of the two-party vote went to Republican candidates, and 4 out of 7 representatives will be Republicans. Colorado’s delegation therefore represents its partisans fairly. (As an aside, it is not required that vote-share and seat-share follow the same proportions. Typically, popular margins translate to proportionally larger seat margins. It’s like the Electoral College.)

In the November election, the following groups failed to meet this minimum representativeness criterion:

D%vote R%vote D seats R seats
Entire House 50.4% 49.6% 201 234
Arizona 45.6% 54.4% 5 4
Michigan 52.7% 47.3% 5 9
North Carolina 50.9% 49.1% 4 9
Pennsylvania 50.7% 49.3% 5 13
Wisconsin 50.8% 49.2% 3 5

In these five states – and in the nation as a whole – the partisan interests of voters are not being represented fairly. Details can be found in a piece by Griff Palmer and Michael Cooper in the New York Times.

Now I will show a way to generalize this point to all states, even in cases when the seat majority and popular-vote majority are out of whack even though they belong to the same party.

Among political scientists, it is often suggested that imbalances like this are not caused by partisan redistricting, but by other “structural” factors such as concentration of Democrats in urban areas. (This is not true. Let’s come back to that later.)

Instead, let’s ask a simple question. If a given state’s popular House vote were split into differently selected districts, what would its Congressional delegation look like?

We can do this by using all 435 House race outcomes. For a state X with N districts, calculate the total popular vote across all N districts. Now pick N races from around the country at random and add up their vote totals. If their vote total matches X’s actual popular vote within 0.5%, score it as a comparable simulation. Because this approach uses existing districts, it uses as a baseline the “structural” advantages that are present nationwide*. In other words, it’s a measure for distortions in representativeness that are specific to state X.

As an aside, note that my approach does not require the drawing of actual districts. Doing that properly requires professional redistricting software and much time. (Update: One disadvantage of my approach is that it includes in its baseline the shift in district partisan bias that happened in 2011 as a consequence of redistricting. So what I am calculating here does not include the across-the-board difference I showed in my pre-election analysis*.)

Here are 1000 “simulated delegations” for Pennsylvania, along with the actual outcome in red.

It is apparent that most possible redistrictings would have resulted in a more equitable Congressional delegation. For outcomes with the same popular-vote split (50.7% D, 49.3% R), 1000 simulations give a median result of 8 Democratic, 10 Republican seats (average, 8.3 D). The actual outcome was 5 Democratic, 13 Republican. In fact, only 1 of the 1000 simulations led to such a lopsided split. And indeed, Pennsylvania legislators are known to have gone to extremes to favor Republicans during redistricting.

How much structural imabalance is there here? In this case, the structural imbalance is 9-8.3=0.7 seats. Partisan gerrymandering added a further imbalance of 8.3-5=3.3 seats. In other words, gerrymandering’s contribution to Pennsylvania’s partisan outcome was about five times as large as the effect of overall structural advantages.

Here is a listing of top offenders for whom the partisan discrepancy was 1.0 seat or greater.

D %vote D sim R sim D seats R seats Discrepancy
Pennsylvania 50.7% 8.4 9.6 5 13 R+3.4
Texas 39.9% 9.4 26.6 12 24 D+2.6
Ohio 47.9% 6.5 9.5 4 12 R+2.5
North Carolina 50.9% 6.2 6.8 4 9 R+2.2
Michigan 52.7% 7.2 6.8 5 9 R+2.2
Arizona 45.6% 3.2 5.8 5 4 D+1.8
Virginia 49.0% 3.7 5.3 2 7 R+1.7
Illinois 55.4% 10.3 7.7 12 6 D+1.7
Indiana 45.8% 3.2 5.8 2 7 R+1.2
Net, all 9 states 48.5% 58.1 83.9 51 91 R+7.1
D-controlled D+1.7
R-controlled R+13.2

The left column is coded by which party controlled redistricting. In black are a court-ordered redistricting (TX) and a nonpartisan commission (AZ). Note that California did not make this list, despite the fact that their redistricting was the focus of a loosely-argued ProPublica article. Basically, California votes Democratic and has a Congressional delegation whose party composition reflects the fact accurately and fairly.

There are some simple lessons to take away from this.

  • Republican-controlled redistricting led to a swing in margin of at least* 26 seats, almost as large as the 31-seat majority of the new Congress. Those actions created a new power reality in the House – or more accurately, retained the old power reality.
  • In the states listed above, the net effect of both parties’ redistricting combined was R+11.5 seats. Putting all of this redistricting into nonpartisan commissions would lead to a swing of at least 23 seats. The resulting seat count would be 213 D, 222 R or even closer. It is possible that in the absence of partisan gerrymandering, control would have been within reach for the Democrats.

I will end today with a graph showing the total effect of Republican-controlled redistricting in six states: PA, OH, NC, MI, VA, and IN.

In the next post I’ll show how to convert these results to an estimate of disenfranchisement, and suggest possibilities for future elections and activism.

Postscript to political scientists: If this topic interests you, by all means be in touch. This is original research. I would welcome collaboration (and priority).

*Update, 7:57pm: By using this year’s vote totals, I am also counting in the baseline the overall shift in partisan voting index (PVI) that took place in this year’s redistricting. In other words, the baseline itself tilts Republican because gerrymandering is still in it – it’s just “scrambled” all over the country. This baseline corresponds to the calculations I did in October and November – that’s why the black points intersect the green line at >50%. The upshot is that the total effects of partisan redistricting are, overall, even larger than what I have highlighted today.

Tags: 2012 Election · House · Politics · Redistricting

52 Comments so far ↓

  • Wheelers cat

    The implication is that that disadvantages democrats- but it is actually enabling a form of hostage taking where repubs only face challenges from the extreme right. The teahadists control enough seats at this point to basically destroy compromise in government.
    So it’s not just anti democratic lack of representation, it’s destruction of function.

  • Valerie M. DeBill

    From the statement, “For some state X, pick races from around the country at random, under the condition that their vote totals still add up to X’s actual popular vote,” I assumed initially that you were using the sum of the actual votes for the state. However, the rest of the post speaks only in terms of percentages. Are your randomly-selected districts adding up to the analogous percentages or the analogous vote counts?

    If you’re using the totals, then I have no further questions, because obviously those would translate into analogous percentages as well and cover both aspects of the model.

    If you’re only using percentages, are you somehow otherwise taking into consideration the population of the randomly-selected districts versus those in the state you’re analyzing?

    Thanks for this analysis: I find it very interesting and compelling. I’m primarily curious about the details because I think they speak to the accuracy of the model, but whether you used the percentages or the votes you have still demonstrated a clear trend.

    • Sam Wang

      Actual votes were used (not percentages) for N_X districts, where N_X is the number of districts in state X. Consequently the total number of votes is not matched. This was used to generate the overall scatter plot.

      Of the results, those within +/-0.5% of state X’s overall percentage were used to calculate the matching simulated outcome.

  • Ken Miller

    Hi Sam,
    Beautiful work! (and congratulations on the wonky!)
    A question on methods: you write “For some state X, pick races from around the country at random, under the condition that their vote totals still add up to X’s actual popular vote.” Obviously easier said than done (picking at random and getting the totals to add up correctly). Could you be a little more explicit on what you did? Thanks!

  • Joel

    Sam, great post. However, your Ohio numbers seem off? Would the Democrats really only pull 6.5 seats in your simulation of random elections? IF that’s the case, then the discrepancy is D+5.5, not the other way around.

  • Marc

    After removing the effect of gerrymandering, we are still left with the fact that the House popular vote was majority Democratic, while Sam’s estimate is majority Republican. That is, 50.4% D, 49.6% R vs 213 D, 222 R. Splitting the 435 seats directly according to the popular vote percentage would yield 219 D, 216 R. So, are we left with the conclusion that there is a six-seat structural advantage for the Republicans?

    • Sam Wang

      Thank you for posting this. Your work is the precedent that has driven the conversation until now. I will cite it appropriately.

      As indicated in the essay here, I think there are problems with the districting claim. The resampling approach that I have used here indicates that structural issues contribute a considerably smaller effect. My calculation also provides a conservative baseline for quantifying partisan gerrymandering effects.

      I currently believe that doing away with partisan redistricting might conceivably have been sufficient this year to give control to the Democrats. The total effects of gerrymandering are the combination of my calculation today, the overall redistricting-driven PVI shift that I wrote about in October and November, and additional incumbent protection effects from redistricting.

      Some of these issues (though not incumbent protection) could be teased out further by using 2010 district results for the simulations.

      To quote Lyndon Johnson, Let us continue.

  • JaredL

    Very interesting stuff. Looking forward to future articles in the series.

    “(As an aside, it is not required that vote-share and seat-share follow the same proportions. Typically, popular margins translate to proportionally larger seat margins. It’s like the Electoral College.)”

    I think this is a bigger issue than it might seem, worth 3 or 4 representatives.

    If you distributed the representatives as close as possible to proportional according to the national vote for each party, it would be D 220, R 215 * according to Wasserman’s numbers and 219/216 according to yours (he has it 50.6/49.4 instead of 50.4/49.6). If you do the same for each state according to how many representatives each has, it flips to D 216, R 219, good for R+4.

    This is because the over-representation effect is larger for smaller states, which tend to be Republican dominated. States where Democrats make up a solid majority tend to be larger which allows for closer to accurate representation.

    The most extreme case, states with one representative, reduces to winner-take-all (which go 5-2 for Republicans) but it extends beyond that. For example, Democrats got just shy of 37% of the votes in Mississippi but even in an ideally fair system that would give them only 1 of the 4 seats. So Mississippi Democrats would have only about 2/3 of the representation their votes merit even in a world where there are no district effects.

    * would be D 214, R 209, other 12 if you take all non-R/D votes as one whole group.

  • Rob Richie


    I’d urge you to read through our detailed analysis of the core problem is single-member districts and the inescapably true fact that the Democratic vote is more concentrated than the Republican vote — as one example, Obama won only 22% of counties this year, fewer than Dukakis won in 1988. See our piece at:

    Note that the Republican bias in districts was nearly as pronounced as it is now in the 1990s, even though Democrats controlled redistricting in far more states than 2011.

    Note further the trends in the Nate Silver piece taking place between redistricting –a pattern that is also remarkable in states in the presidential race, with state lines of course not changing.

    • Sam Wang

      Let me briefly clarify and moderate my statement.

      I think it is likely that population patterns constrain districting in ways that favor Republicans a little bit on average, which I believe is your point.

      For purposes of governance, which as a citizen I care about quite a lot, I want to know the the bottom line for a voting majority. In other words, what is the net effect on the total caucus?

    • Rob Richie

      Thanks for the quick reply, Sam.

      What we found is that going to multi-seat districts of between three to five districts with a non-winner-take-all voting makes it exceptionally easy to remove bias — with such an approach being statutory and grounded in our own history and local practices. Check out our simulation of such plans at FairVoting.US

      Count me as a huge skeptic that redistricting commissions done nationally with reasonable criteria (including preserving communities of interest and upholding the Voting Rights Act) would come close to removing bias.

    • Sam Wang

      I agree that multi-representative districts are a potentially good idea. I don’t see that happening in the near future, at least not in the states I have highlighted today. And I do have some concerns about constituent services in the system that you advocate.

      I am focusing on partisan gerrymandering because that is a current crisis that must be addressed soon. There is a fire to be put out!

    • Steve Chessin

      Sam: Your concerns about constituent service can be addressed by the use of a mixed-member PR system, such as used by Germany and New Zealand. MMP combines single-member districts with at-large seats in a way that guarantees proportional results.

  • Some Body

    Fascinating approach!

    Some remarks:

    1. Interestingly, your results are not actually saying something that different from what the Monkey Cage people or Nate Silver are saying. You agree with the original Monkey Cage piece that even without gerrymandering, there House should have gone Republican this year, despite the Dem popular vote majority, and Nate didn’t claim full symmetry (he also thought the effect is significantly more pronounced on the Republican side, and correctly singled out Illinois as the one state in which the Dem side benefits from redistricting the most).

    2. The really intriguing results in your table, for me, are actually the ones for Texas and Arizona. Could it be that when impartial bodies determine districts according to fair principles, their measure of fairness is significantly more favourable to Dems than the one you’re using? I guess we should look at more states where neither party drew the lines to tell.

    3. One possible argument against your method is that structural factors are not evenly distributed among the states. Pennsylvania illustrates that well: you basically have Philadelphia and Pittsburgh as Dem strongholds with lots of deep red territory all in between. And while the Democratic vote is usually concentrated in and around big cities, the contrast in PA is more extreme than in most other states I can think of (mostly because of the size of cities in question). So that would be an argument for saying that your method understates the structural disadvantage Dems have in PA.

    • Sam Wang

      Thank you for your comment. After thinking about what you wrote, I realize that my baseline itself contains the overall shift in PVI that occurred with redistricting. In other words, I am spreading the full effect of gerrymandering over two calculations: my pre-election calculation, and this one today. The true effect is their combination.

      Comments #1 and 2: after thinking…I don’t necessarily agree. Today, I implicitly left out the 1.2% tilt in the playing field that I wrote about before the election. In the absence of partisan gerrymandering (including the aspects that include incumbent protection), the Democrats might have won control…barely.

      Comment #3: I don’t think this holds up well. For instance, New York was redistricted by a court-appointed master (Columbia’s Nate Persily, who is visiting Princeton this year). I did not find a problem there.

      I think the main effect of structural issues is not partisan unfairness. It is quite possible to draw districts that are fair in the partisan sense. What is harder is to draw districts that are competitive and reflect the interests of various constituencies. In my view, the structural=partisan equation is at best a minor point.

    • Some Body

      And thank you for your response! (which I only saw now; was travelling)

      I agree with what you say (and can’t argue about other non-partizan redistrictings, because I don’t have the full data). I’d only note one point about incumbency benefits: for the 2012 election they didn’t yet reflect the effects of the 2010 redistricting (incumbents were elected in 2010, by 2000 lines).

      One more question – if you also include the incumbency baseline in the calculation, will you still have Illinois, Arizona and Texas with a significant Dem “skew” in your table? Not sure if that’s easy to answer without looking at local data for each state though.

    • JonF

      But New York is not equivalent to Pennsylvania. There’ s no “Pennsiltucky” in New York: the rural areas may skew a bit conservative (note: I have friends in rural Chautauqua county, and also up around Warsaw, so I have some direct familiarity with this), but nothing like the way that large parts of Pennsylvania replicate the political attitudes of West Virginia, Kentucky and Tennessee. And most of the conservative resentment in New York is based on resentment of New York City; it does not express itself so much in the larger set of racialist and faux-libertarian resentments of Tea Party Republicanism, which leaves many people in New York quite cold.

  • Quinn

    This is fabulous data. Clearly it shows that the worst offenders for this redistricting round were GOP controlled state houses. That being said, I’m not sure that it busts the myth that both sides gerrymander as much as it shows how important the state house results in the 2010 elections were and the magnitude of that control. Illinois still had a D positive discrepancy (if not as big as Pennsylvania). If 2010 had been a big swing election for Dems at the state level, is it not likely that more states would also have had a D positive discrepancy and rode a perceived mandate to similar magnitudes?

  • Dave Kliman

    The problem here really multiplies when you take into account that these highly gerrymandered districts also yield a highly lopsided state legislature. Take for example Florida (senate: 26R 14D; house: 74R 46D). That’s what gerrymandering does in a state where the democrats won the popular vote. I wonder, in the wake of all this extreme redistricting, if it will ever be possible for democrats to control that state again.

    Now Michigan (senate: 26R 12D; house: 59R, 51D) is like Florida, in that manner. Democrats won the popular votes in both states, but now that the legislatures are controlled by artificially created republican majorities, they will make sure to pass whatever legislation such as voter suppression law is necessary while selecting highly partisan judges to uphold these laws, just to increase and consolidate their long term position of power.

    • Dave Kliman

      oh and let’s not forget that they decapitated the democratic get-out-the-vote machine of the unions by passing right-to-work-for-less legislation that will erode the democrats’ only mechanism to do battle with the oligarchical right wing billionaires and their unlimited money to swing any race from dog catcher to the top.

    • JonF

      State legislatures do not appoint federal judges, and ultimately vote suppression suits will be heard in federal courts (perhaps even in the Supreme Court). As we saw in this year’s election, vote suppression tactics rarely pass judicial muster, unless they are so weakly structured as to be ineffective at suppressing partisan vote.
      There’s less danger of this than many Democrats fear– especially since Obama will be appointing four more years worth of federal judges now.

  • Fred Silverman

    Interesting Fla is not on the list. But even more so gerrymandering that keeps the state legislature itself locked up by one party. How can Fla elect a Dem. Senator & Obama, but wind up with a state legislature 60-66% GOP? Its in the legislatures themselves that these fun games begin.

    • Joel

      @Fred, one might imagine that voter participation rates play a role. Florida would be an extreme case, with a large population of elderly, highly participating voters.

  • Steve Chessin

    I think one point you’re trying to make is that single-member districts do not produce proportional results. Well, duh! For example, suppose you had a state where Democratic voters and Republican voters were uniformly distributed, so that no matter how district lines were drawn, the relative proportion of each party (by vote) within each district matched the statewide proportions. (That is, if the statewide vote was 52% R/48% D, so was the vote in each district.) Then whichever party had more votes (in this example, R) would win all the seats.

    Partisan gerrymandering does exacerbate the problem; but that’s because we use single-member districts. Since a party needs only slightly more than half the vote in slightly more than half the districts to elect a majority of the seats, a minority of slightly more than 25% of the voters can dominate the majority. (Multi-member districts using proportional representation raise this threshold of control. For 3-seat districts, it becomes 37.5%; for 5-seat districts, it becomes 41.7%. This makes it harder to draw lines that disproportionally favor one group.)

    If you want to have proportional results, you either have to do a(n oxymoronic) “fair gerrymander”, where you draw lines that guarantee a pre-determined result that you think is proportional to how people will vote, or else you bite the bullet and institute proportional representation (PR).

    Despite popular misconception, instituting PR does not require a constitutional amendment. All we need to do is amend 2 USC 2c to allow states that elect more than one representative to use a PR system to do so.

  • Peterjk23

    I’m an Australian, so forgive me if I’m wrong, but might not the Voting Rights Act itself be a cause for some of this bias. My understanding is that it required the creation of minority, majority districts. Given that the minority vote is overwhelmingly democratic, dosent this lock up democratic votes in ultra-safe districts, rather than spreading them around where they would be much more effective?

  • Steve McCluskey

    The apparent logical flaw in your argument is where you say that in Pennsylvania “the structural imbalance is 9-8.3=0.7 seats. Partisan gerrymandering added a further imbalance of 8.3-5=3.3 seats.”

    I don’t see it as that clear. The 3.3 seat diff you attribute to gerrymandering is clearly due to a process in PA that concentrates Dems in a few districts more than in other states. The formal analysis doesn’t tell us the extent to which PA’s difference is caused by gerrymandering and the extent to which it is caused by the concentration of Dems in a few urban areas.

    Nice work in progress—I look forward to parts 2 & 3….

    • Sam Wang

      There’s no logical flaw. It is not hard to draw district boundaries more fairly. For one thing, they were more fair before 2010. For another, other large states have done it. The structural thing is way overblown.

    • Steve Chessin

      Sam, please define what you mean by “fair district boundaries”. Your examples seem to stress proportionality: “As an example, consider Colorado. There, 51.4% of the two-party vote went to Republican candidates, and 4 out of 7 representatives will be Republicans. Colorado’s delegation therefore represents its partisans fairly.”

      “In the November election, the following groups failed to meet this minimum representativeness criterion:
      D%vote R%vote D seats R seats
      Entire House 50.4% 49.6% 201 234
      Arizona 45.6% 54.4% 5 4
      Michigan 52.7% 47.3% 5 9
      North Carolina 50.9% 49.1% 4 9
      Pennsylvania 50.7% 49.3% 5 13
      Wisconsin 50.8% 49.2% 3 5

      In these five states – and in the nation as a whole – the partisan interests of voters are not being represented fairly. ”

      “California votes Democratic and has a Congressional delegation whose party composition reflects the fact accurately and fairly.”

      So what do you mean by “fair”, if not representation in direct proportion to how people vote?

    • Sam Wang

      “Fair” = according to standards in nearly all other states according to current standards of districting, as resampled in simulations.

      Proportionality of seats to votes per se does not interest me. That is a hypothetical good-government scenario that is not the current standard of how the US determines representation in the House. I regad it as either academic or a reform that is unlikely to happen soon, if ever. I’m an academic…but right now the house is on fire.

  • Amitabh Lath

    So the basic idea is that the total number of congressional districts (435) is a “large” number. If you pick randomly from this set, you don’t have to worry about internal correlations.

    Can you come up with a metric (distance from the best-fit line for the observed outcome?) that scores each district’s gerrymanderedness? This value should anti-correlate with lopsided vote margins for the other party in neighboring districts.

  • Amitabh Lath

    Gerrymandering by a party (say, Republicans) also creates
    very safe Democratic seats. It is in an individual Democrat’s
    interests to help the Republicans gerrymander, even though
    collectively the Democrats suffer.

    I’m sure there is some game theory thinking that applies,
    but I don’t know much about that stuff.

    If this is so, then it becomes even more difficult to fight
    gerrymandering, because you are bucking established Dems
    who would see their districts level out.

    • Wheelers cat

      Min-max theorem. Like the Sailer Strategy the GOP used in the election. Maximize the citizens that will vote for you, minimize those that won’t.
      Ideally districts should be fractals of the state. I wonder if one could use projective geometry to draw districts.

    • Liam

      That’s right. And his name is Bob Brady.

  • Ed Hannon

    Absolutly briliant work. Is there a way to split the two present day factions of the republican party (GOP and TEA) and provide separate proportional popular vote data for each by state? When it comes to things like filabusters in the senate and caucus support in the house the difference between the GOP and TEA parties can loom large with reguard national policy maters.

  • Bill de Lara

    Historically, the democrats started redistricting for the purpose of achieving a laudable goal- the creation of black districts that will enable black representation. The unintended consequence is that redistricting is now being used by republicans to create as many safe republican districts as possible.

  • Sam Wang

    To “” (so clever): Look up the popular vote in Maryland, which was 65-35 this year. Very unfavorable for the minority party.

    If you resample districts across the country, this vote share leads to an average split of 6.2 D to 1.8 R. Compared with 7 D, 1 R, this does not make the 1-sigma criterion. Consistent with this, the one Republican race does not have a margin out of proportion to the other races.

  • Connor Allen

    Sam, I appreciate your take on this. I think you have a number wrong, though. Doesn’t Virginia have 3 Democratic members of Congress? Jim Moran, Bobby Scott, & Gerry Connolly?

  • Bob

    On the other side of the coin, I live in Maryland, where, thanks to some *ahem* creative district boundaries, we have 7 Democrats and 1 Republican representing us.

    However, I do agree with the premise that gerrymandering by either party is bad, and it does lead to more partisan congress.

  • Chad Hall

    The Florida LWV just succeeded in a long fight to redistrict there. I posted about this on my politics blog:

  • Robert Maxwell

    Sophisticated and convincing. You’ve got the sort of results, contentions aside, that really should be picked up by the mass media and practically never is. Same with Rosenthal and Poole.

  • Spa K

    Both sides do it. That is not a myth.

    One side (Repub) has done more gerrymandering RECENTLY but Dems have done their share in the past, and want to do it again in the future. That’s the problem. The Democratic Party has no interest in fixing this problem because our side wants the ability to cheat with gerrymandering again in the future.

    “Both sides do it” still stands. The people need to fix this problem because Congress won’t. It’s like asking them to stop giving themselves raises. Ain’t gonna happen.

    • ogates

      The 27th Amendment protects Congress’ salaries. Isn’t that the problem–that our lawmakers, the true “elitists”, enjoy protections, benefits and power while the populace is left to deal with the consequences of their “party first” mentality?
      Congress are the wolves in charge of the sheep who are all too willing to go over the cliff in the name of political party, i.e., the 2016 government shutdown! Cost: 24 billion! A total waste of money that could have been used to create jobs to fix our infrastructure.
      A small group of extremist have taken the House on the Hill hostage! Now–how to fix it?

  • ogates

    We agree–the country has been gerrymandered to the extreme. My question is how do we reverse this republican trend and restore democracy and make our vote count?

    • dave

      According to the article (the one above) the Supreme Court said that the people of each state can have a ballot initiative for an independent group to draw up the districts. That can be done how. The People don’t have to wait until 2020.

    • Frank

      Take the redistricting out of the hands of the legislators and give it to an independent body.

  • Sam Turner

    I would like to highlight the fact that state legislatures are not only responsible for redrawing Congressional districts but also their own state’s General Assembly lines. They are drawing the lines to the very districts that will vote for them, ensuring their re-election. This is blatant corruption. (I live in NC and am very upset.)

  • Frank Carr

    Your basic premise is faulty: Our government is not like Germany’s, where votes guarantee seats regardless of geography. Congressmen represent geographic locales.

    Democrats hyper concentrate in cities, where 90%+ margins of victory for the Democrat are common, while Republicans form small majorities in suburbia. Your metric ignores this fact and overstates the effect.

    • Sam Wang

      Frank Carr’s statement is factually wrong and somewhat deceitful. But I will allow it anyway because surely there are others who believe this. Also, he appears to have left a real name and address.

      Geographic sorting is *not* sufficient to account for lopsided wins. It is a starting material, which can then be used by partisans. This is why the partisan division of Michigan, North Carolina, and other states jumped abruptly, immediately after 2011 redistricting. See

      As for overstatement of effects, that is why we do the Monte Carlo simulation of excess seats. This captures the normal give-and-take of redistricting, as well as human geography.

      Finally, Carr makes the assertion that “Congressmen represent geographic locales.” This is literally true but misses the point that there are many ways to divide a state into districts. Redistricters have enormous discretion and have to deal with ideological and ethnic diversity. It is deceitful to pretend that line-drawing does not matter.

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