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North Carolina’s Second Route to Redistricting Reform

September 4th, 2018, 10:47am by Sam Wang

The path to redistricting reform in North Carolina has gone through federal courts – but looks shaky at the moment. New in the Washington Post, Rick Ober and I point out a second path, through state courts. This second path does not require a federal standard!

Also in the Post, here’s a beautiful visualization of the causes and consequences of the Tar Heel Gerrymander.

→ 3 CommentsTags: Redistricting

We drew a fairer map for the Virginia legislature – and so can you!

August 30th, 2018, 12:40am by Sam Wang

A federal court has ordered the Virginia legislature to redraw 33 districts in the eastern part of the state, in order to undo a racial gerrymander. The Princeton Gerrymandering Project is pleased to announce its first open-data project. Ben Williams and Will Adler drew a proposed map for them. Explore it through our interactive above (bigger view here). Also, we are giving out the data needed for people to create their own maps! [Read more →]

→ 6 CommentsTags: Redistricting

Optimal Donations 2018: Senate and Governor’s races

August 26th, 2018, 4:40pm by Sam Wang

In 2016, I promised to get away from giving you probabilities. Here I show that under current conditions, you can optimize your donations without such calculations.

As has been the case in past elections, I’d like to point out key races where supporters of either Democrats or Republicans will get the maximum impact for their donation. (I’m assuming that control of either chamber of Congress has comparable value – see reader James McDonald’s point.)

This year, I don’t recommend giving to House races for two reasons.

  • There are just too many of them. Over 80 districts are less Republican-leaning than Ohio’s 12th district, whose margin was razor-thin in the recent special election. Compared with the six key Senate races I’ve listed at left, your donations would be diluted by more than a factor of 13. This is the big reason.
  • Under current conditions, we are closer to threshold for switching Senate control than for switching House control. Therefore Senate control is closer to the knife’s edge.

Taken together, these two reasons dilute the impact of your donation by a factor of 30-100*. This can change, depending on how the overall odds of House or Senate control change over the next two months.

Instead of giving you probabilities, which leads to possible complacency, I will simply ask: how far are Democrats/Republicans from threshold for House or Senate control? [Read more →]

→ 24 CommentsTags: 2018 Election · governors · House · Redistricting · Senate

Thomas Hofeller, 1943-2018

August 19th, 2018, 9:59am by Sam Wang

Despite the near-certainty that Democrats will win the national popular vote for House races in November, I still estimate a 10% probability (and other forecasters, up to 25%) that Republicans will retain control. Why? Gerrymandering.

More than anyone else, Tom Hofeller was responsible for the modern age of aggressive redistricting. He carried out this program to an extent that nobody in either party had ever done before. To get an idea of how his work altered and eroded American democracy, see this Atlantic profile of his work. Reid Wilson writes about his life in The Hill.

Comments Off on Thomas Hofeller, 1943-2018Tags: House · Politics · Redistricting

The Authoritarian Checklist – John Brennan / Peter Strzok update, August 2018

August 15th, 2018, 3:35pm by Sam Wang

I’ve left this topic alone for some time, but we must revisit it every time one of the items is checked off in a major way. On August 15, it’s Trump’s targeting of government officials Peter Strzok at the FBI and former CIA director John Brennan. Those enlarge the list of offenses under item #5 below. [Read more →]

→ 27 CommentsTags: President · U.S. Institutions

OH-12 is ominous for GOP in House…and the Senate

August 7th, 2018, 11:36pm by Sam Wang

At the moment, in the special election in Ohio’s gerrymandered 12th district, Republican Troy Balderson leads Democrat Danny O’Connor by 0.9 percentage point (with 0.6% of the vote going to the Green Party candidate). This is a loss for Democrats, but it’s a 10-point swing from the Clinton-Trump margin in 2016. That’s very much in line with special elections all year, and it has implications for November.

In 46 special elections in 2018, the overall swing from 2016 has averaged 12 points toward Democrats. Hillary Clinton won the national popular vote by a little over 2 percentage points. If this swing were to hold up in November 2018, it would mean a 14-point win in the national House popular vote. I estimate that a 6-point win would be just enough to flip control. A 14-point win is massive, enough for a gain of over 50 seats.

Another piece of evidence points toward a building Democratic wave: Harry Enten of CNN has pointed out that Democratic pollsters are reporting their internal polls far more often than Republican pollsters. This observation corresponds to a minimum gain of 30 seats for Democrats. It’s hard to tell the ceiling because the D/R ratio has not been this high before.

As for the generic Congressional poll? Mostly ignore it. Even in the home stretch it misses some aspect of public opinion, probably because midterm turnout is hard to estimate. However, I will note one thing; it’s currently showing a lead of about 7.5 percentage points for Democrats – much less than implied by the two indicators above. If polls are underestimating election-day Democratic support, any discrepancy is important for close Senate races in Tennessee, Texas, and elsewhere. Recall that Senate polls in 2014 were off: in that case, Republicans overperformed against a Democratic incumbent president. Now the shoe is on the other foot.

What can you do this year? Whether you are a Democrat or a Republican, my advice is the same:

  • Near you, find a competitive House district and get out the vote there. Use the PEC-sponsored district finder!
  • Elsewhere in the country, donate to the most competitive Senate races. I curate these here.

And what if you’re a third-party voter, like the 0.6% who voted for the Green Party in OH-12? I’d say you lack situational awareness of what it means to live in a two-party system. Might be time to rethink that attitude.

→ 9 CommentsTags: 2018 Election

Optimizing Your Efforts in 2018: Part II, the Senate

August 2nd, 2018, 1:04am by Sam Wang

PEC High-Impact Races for 2018
In 2018, what’s a swing state? In many cases, it’s not the swing states that everyone focused on in 2016. How should you optimize your activism and donations? tl;dr: You can donate via the PEC ActBlue page (if you like Democrats) or the NRSC (if you like Republicans).

The reason for the difference from 2016 is obvious: this year’s big questions are not the Presidency, but who will control the House, the Senate, and governor’s mansions and legislatures. In some cases, the hot races are still in purple states (Nevada, Florida), where the statewide vote is closely divided. But just as often, maybe more so, regional factors matter.

For example, Indiana is strongly Republican in its Presidential voting, yet Senator Joe Donnelly (D) beat the eccentric Richard Mourdock (R) for a Senate seat six years ago in 2012, a somewhat-good year for Democrats. This year, Donnelly has a fighting chance to retain his seat. More broadly, current polls indicate six knife-edge Senate races: Nevada (D-Rosen v. R-Heller), North Dakota (D-Heitkamp v. R-Cramer), Missouri (D-McCaskill v. R-Hawley), Florida (D-Nelson v. R-Scott), Indiana (D-Donnelly v. R-Braun), and Tennessee (D-Bredesen v. R-Blackburn).

Not counting these races, Democrats are favored to end up with 46 seats, Republicans with 48. To take control, Democrats would have to win five out of the six knife-edge races. This is a tall order but not at all impossible. Races that look close at this point in the season tend to end up breaking in the same direction. For a probabilistic look, see David Byler’s Senate election model.

In addition, one might keep an eye on the Arizona and New Jersey races, though I think Democrats will likely win both. Conversely, Texas is still looking like a Republican hold, at least for now.


After you’re done donating, you can also look for a place to campaign near you. Door-to-door campaigning is by far the most effective known way of increasing turnout. Swing districts are all over the United States, as you can tell by looking at our 2018 Competitive District Finder.

→ 4 CommentsTags: 2018 Election · Senate

Support the Princeton Gerrymandering Project!

August 1st, 2018, 12:00pm by Sam Wang

The Princeton Gerrymandering Project does nonpartisan analysis to understand and eliminate partisan gerrymandering, which has soared since 2011.

Starting in 2018, we now do most of our work at a local level. Although the Supreme Court acknowledged the validity of our math (see our great explainer video), they still probably won’t act. State-level action can fill the gap through court cases and citizen initiatives. We help understand how proposed reforms connect to actual outcomes, using rigorous analysis and legally admissible maps. Our analysis is published widely, and our work is used by legislators and reformers of all communities, without regard to partisan affiliation.

This analysis requires intensive data-gathering, statistical analysis, and legal scholarship. All this costs time and money. If you are interested in supporting us, you can make a gift onlineIMPORTANT: In the special instructions field, paste the following: “S. Wang research on gerrymandering (PN0019) Account 24400-B0996-FA508”. You’ll receive an acknowledgement email; feel free to also email us separately at to let us know.

Thank you for your support!

Comments Off on Support the Princeton Gerrymandering Project!Tags: Princeton · Redistricting

Stop Partisan Gerrymandering With These Three Weird Tricks

July 16th, 2018, 3:29pm by Sam Wang

When it comes to partisan gerrymandering, the Supreme Court whiffed. The road ahead for federal action is not looking great. However, that doesn’t mean it’s game over, as we reported today in The American Prospect. In fact, there’s considerable hope.

We looked into the laws, constitutions, and political landscape in every state where there’s currently an extreme gerrymander. In every case we found at least one remedy. In North Carolina, it’s the state constitution. In Maryland, it’s the possibility of a bipartisan process. And in Michigan, there’s a powerful voter initiative.

Read our detailed state-by-state analysis!

→ 8 CommentsTags: Redistricting

Optimizing Your Efforts in 2018: Part I, the House

July 14th, 2018, 10:48am by Sam Wang

The odds moderately favor a switch in control of the House of Representatives in 2018. But make no mistake, things could go either way. This November will be a battle of inches.

For many of you, the battle’s coming to a district near you. We’re renewing a tool that made its debut two years ago. Sharon Machlis has very kindly updated her Congressional District finder to display swing districts for 2018. It’s awesome – check it out!

Many of the closest races will be run in the suburbs of America. Here are some high-value areas:

  • Six swing districts are within 100 miles of New York City.
  • Five are within 50 miles of Los Angeles.
  • Five are within 50 miles of Chicago.

Note that this tool is useful no matter which major party you favor. The same districts are targets for flipping – and prizes worth defending. So if you have any interest at all in the direction of this country, this resource is for you.

By campaigning or donating in close races, you can have many times the impact that you would by voting alone. Anyone in the United States can get involved – not just citizens, but also foreign nationals (see the Federal Election Commission website).

Soon we will merge this functionality with information about statewide races: Senate, governor, and initiatives. That’s part of a site upgrade that is in the works. Soon, my droogies, soon…

→ 7 CommentsTags: 2018 Election · House