Princeton Election Consortium

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In time for the equinox, is the Summer of Trump waning?

September 21st, 2015, 1:59pm by Sam Wang


In time for the autumn equinox on Wednesday, the Summer of Trump is waning. Surveys are now out with samples entirely postdating GOP debate #2. Taking a median of the last 4 pre-debate polls gives Trump 33.0±0.7% (estimated SEM). Then, in the last 4 pre-debate polls, Trump is now at 26.5±3.0%. The combined uncertainty (sigma) is 3.1%. He has dropped by 6.5%, which is greater than two times sigma and therefore statistically notable. Where does this end? Has Trump peaked and will he continue to head down? It’s hard to say .

Note that the HuffPollster graph above is shown just to give a visual impression, not for extracting the numbers I give above. As useful as HuffPollster is, their smoothing algorithms tend to boost the size of swings in the last few data points. “Less smoothing” gives the closest result to the simpler calculation of medians, which is why I show it.

The fraction of GOP voters willing to go with outsiders who have never held office (Trump, Carson, Fiorina) still adds up to over 50 percent, but they have redistributed a bit. Considering Fiorina’s problems with accuracy and her dismal performance as Hewlett-Packard’s CEO, it seems likely that her rise will also be transient. If 2012 is a guide, she will last one or two months then fade, just as Cain, Gingrich, Santorum, and Bachmann did. And now, maybe Donald Trump – though his unique combination of issue stands (maintained domestic programs and extreme nativist attitude toward immigrants) and his persona could keep him from dropping all the way. It seems likely that many Trump/Carson/Fiorina voters will eventually turn to establishment candidates…but who?

Walker’s fallen below 2% [P.S. and has dropped out] and Jeb! is stuck around 8%, for now anyway. Assuming those trends persist, the highest-finishing serious candidate is Marco Rubio. As I have said before (link to The New Republic), Rubio is a relatively likely consensus candidate. In the past, the GOP has usually settled on a strong general-election candidate. Rubio polls relatively well against likely Democratic nominee Hillary Clinton. If the past is a guide, then at some point party donors/actors and primary voters may fall into line.

Tags: 2016 Election

39 Comments so far ↓

  • bks

    For a good time, click on Sam’s Huffpost graphic at the top of this entry.

  • bks

    Trump has now been on top of the polls, nationally and state-by-state, for about the same amount of time as remains till the Iowa Caucuses.

  • bks

    Less than one Friedman Unit till Super Tuesday.

  • 538 Refugee

    Wow. Boehner not only giving up the gavel but his seat. Cue hard right turn or is there a scandal looming?

    http://www.nytimes.com/2015/09/26/us/john-boehner-to-resign-from-congress.html

    • Sam Wang

      My guess is a hard right turn. Not really what the GOP should want at this point…or the U.S. more generally, I would think.

  • Stuart Levine

    Am I being overly partisan by interpreting your phrase “Fiorina’s problems with accuracy” to mean her “pathological lying.” Or, should it just be “the fact that she’s fact-challenged.”

  • Amitabh Lath

    New polls by Fox, Qunnipiac, Bloomberg have Trump in the low to mid 20′s. A real decline, or were the highs of late August a fluctuation and this is his steady-state?

    Caveat on Quinnipiac: Shows Carson, Fiorina beating Clinton in a head-to-head. Makes you wonder about sampling bias.

  • Matt McIrvin

    Trump’s decline looks like more of a plateau now; the drop seems to have been largely the effect of that one Gravis Marketing poll. Gravis is probably worth filtering out if the available data are meager.

  • Matt McIrvin

    TPM had an interesting article about how, when they ask two-candidate head-to-head questions in Iowa about Republican primary candidates, everyone beats Trump except Jeb Bush.

    http://talkingpointsmemo.com/polltracker/public-policy-polling-iowa-september

    That suggests that, for the case of Iowa at least, the Republican field could defeat Trump if support were to consolidate behind one other contender. But it’s far from doing that.

    • Matt McIrvin

      …Also, of course, Iowa is a caucus, and I figure those tend to be more tilted toward very politically engaged people, who are not Donald Trump’s core audience.

  • Amitabh Lath

    Sam, I’m not seeing “Trump wanes” from the plot you are showing. If you take away the thick red line and just leave the dots (which have no error bars so I’m going to assume they all carry the same weight) then it looks like a curve with a fast rise in the July-Aug period and reaching an asymptote in September.

    If forced to choose a function I would bet on a 1-exp(-x) or something.

    So, I don’t know why the fat red line dips down at the end, unless somehow that last red dot corresponds to a huge polling sample.

    • bks

      Sam selected “less smothing”. Selecting “more smoothing” paints a different picture.

    • Amitabh Lath

      Ok. I see that a new poll by some firm called Morning Consult has come in with Trump at 32%. I picked the same time frame as Sam, but chose “moderate” smoothing and instead of the red curve dropping off I get a curve that looks like it is reaching an asymptote at little above 30-ish.

    • Sam Wang

      I actually don’t like their smoothing algorithms, which tend to amplify small fluctuations at the end. However, “less smoothing” gives the closest result to what I would deem statistically usable.

      Instead of any smoothing, do the following: take a median of the last 4 pre-debate polls to get Trump 33.0±0.7% (estimated SEM). Then, in the last 4 pre-debate polls, Trump is at 26.5±3.0%. He’s dropped by 6.5%.

    • Matt McIrvin

      I’ve been wondering about that “Morning Consult” operation; I don’t recall seeing them before, and their numbers seem to often be at some variance with other polls.

    • bks

      BTW, the 30+ asymptote is characteristic of the 2011-2012 GOP polls, regardless of the frontrunner, including for Romney in January of 2012.

    • bks

      The Morning Consult poll is new to me but the only poll that should not be in the graph (IMO) is the Gravis Marketing instapoll that only polled Republicans who watched the debate.
      Here’s my graph of the last three months using only live telephone polls:
      http://tinyurl.com/pecpoll

    • Sam Wang

      Can’t cherrypick. Where does that stop. Also, Gravis was first. Therefore that’s the only survey that is guaranteed not contain a herding effect.

    • bks

      Okay, here’s the same graph but including all polls:
      http://tinyurl.com/pecpoll2
      Same, same. I do agree that there has been a Trump downturn.

  • joe

    Bernie supporters are confused and suspicious of the recent Iowa poll that shows Bernie far behind after two polls had him in the lead. One explanation was that it polled “usual voters” rather than “likely voters”. I’d really like to know your take on it, Sam.

    • bks

      I support Bernie, but I have no illusions that all that stands between him and the nomination is skewed polls. That dog won’t hunt. I think it should be pointed out that despite all the pundit-talk about Cain, Bachmann, Perry and Gingrich, Romney won a number of polls in September 2011, including NH, AZ, MI, OH, PA, IA, FL and a Fox national poll.

  • Matt McIrvin

    One of them is Gravis Marketing/One America News, which is historically terrible. The roughly similar result from the CNN poll makes it interesting, though.

    • Insidious Pall

      Carson and Fiorina will descend as well; probably by Christmas. Rubio is on the ascent at the right time and he leads Clinton fairly substantially in the swing states, Michigan, and Ohio.

  • Amitabh Lath

    NY Times reports Scott Walker quitting the race. The news is going to be all about how Trump drove him out.

    There is no other candidate occupying the “I’m not in thrall to billionaires, and I will raise taxes on the rich” space. Walker was almost the antithesis of that, with a visible cord connecting him to Kochs. Trump will feast on his demise, I expect his numbers to go up again.

  • SRS

    I really wouldn’t be so quick to declare the death of Trump.

    If he was dropping to Bush or Rubio I’d agree, but as you point out he’s dropping in a field where the outsiders (Fiorina, Carson, Trump) hold over 50% of the vote.

    Are you really going to say you don’t think Trump can beat Fiorina and Carson?

    We won’t know for sure until people have actually voted in primaries. But what we’ve seen is that the anti-establishment sentiment is real, and it is large. I would not be so quick to just assume the establishment is going to rally and win eventually.

    • 538 Refugee

      This is getting interesting and I’m just enjoying the spectacle myself, but the machine is still in place. There was a link in another thread suggesting the machine gerrymandering of the primary process may be backfiring on them though. I’m still investing heavily in popcorn futures at this point. ;)

    • SRS

      Replying to myself to add some things after reading the CNN poll itself (here: http://i2.cdn.turner.com/cnn/2015/images/09/20/rel10a.pdf).

      Trump has a 52% favourability rating amongst Reps. Imo that is important because it means there are enough Republicans who like him to give him a majority if they all voted for him.

      It’s a bit speculative of me and not based on polling, but to give a bit more sense of where I’m coming from: I think Trump isn’t some temporary fling like we’ve seen in the past, but is drawing on a very real voting block that up till this election cycle was largely being silenced. The disgruntled anti-immigrant anti-establishment but actually kinda pro-government pro-welfare right-winger. The exact same demographic that has fuelled the right wing anti-immigrant demagogues that have risen up in Europe.

      Based on that, I’m predicting that Trump is going to keep his 20+ percent of support all the way till the primaries start. The question is, what’s going to happen once the field starts dwindling? If the non-Trump vote is all establishment, than I can imagine it will coalesce around an establishment candidate and nominate that person (Rubio or Bush prob, imo). But right now what I’m seeing is that a sizeable part of the non-Trump vote, a majority, is still rejecting the establishment candidates. So I think there’s a reasonable chance Trump is going to come out on top by beating the alternatives. (I think Trump winning will be mostly about Trump beating his opponents because his opponents turn out to be weak.)

    • Craigo

      “Are you really going to say you don’t think Trump can beat Fiorina and Carson?”

      Why assume that his main competition will be Fiorina and Carson, who – as Sam points out – bear a striking resemblance to the clown parade of 2012 “frontrunners”? Anti-establishment feeling was real and large then too – but smart money is on an establishment candidate, as it always was.

    • bks

      I’m waiting a fortnight before declaring peak Trump.

    • Matt McIrvin

      2012 was a bit different in that, while the clown-car candidates all took their turns, Mitt Romney was always still there in a strong #2 slot with a substantial chunk of support. Trump has bigfooted any establishment candidate’s chance to do that early on.

      The return of Rubio is interesting because he was considered a serious candidate by the serious people early on (and was a front-runner for a while last year). So this could be the beginning of the establishment politicians coming back, or it could just be him.

    • Matt McIrvin

      Also, other polls still seem to be giving inconsistent information on Rubio; unlike Fiorina it’s not so clear that he’s surging.

  • poliforecast

    “If the past is a guide” the nomination will go to a white male. That’s Jeb!. Just putting my marker down.