DONALD TRUMP’S poll numbers are slipping in Iowa, and a new national poll is the first in a while to show him trailing. But a closer look at the polling suggests that the Trump wave may have been overstated from the beginning. His sizeable lead has been based largely on the influence of Internet polls. Trump’s summer surge looks far less impressive in telephone polls, and polls of likely voters show his lead was always smaller and is now gone entirely.
Looking across all pollsters and modes of pollsters, Donald Trump leads the field by 10 points, according to the Huffington Post, which averages poll results.  Using only online polls, his lead is even bigger. But narrow the field to just telephone polls, and Trump’s lead over Ben Carson drops to 3 points. Drill down further to phone surveys that talked only to likely voters in the Republican primary, and Carson actually overtakes Trump.
The same dynamic is playing out at the state level. In online polls, Trump is tied with Carson in Iowa, and clobbering him by 26 points in New Hampshire. The telephone polling in both states is markedly different, showing Trump now trailing Carson by double digits in Iowa and leading by half as much in New Hampshire.
Online polls are still relatively new, especially for presidential primaries, but their performance in the 2012 cycle suggests they may exaggerate the rise of surge candidates. Herman Cain, of 9-9-9 fame, owed his entire lead to online polls. Looking only at telephone polls, Cain’s lead shrank from 14 points to just 1 point. The same dynamic was present with both Rick Perry and Newt Gingrich, though to a lesser extent.
Fast forward four years, and online surveys make up a much larger share of national primary polling and once again are producing different results. This has had the effect of further boosting Trump, since online polls are now playing a bigger role in the overall average used by poll aggregators. So far this cycle, nine online polling outfits have conducted almost half of all presidential primary polls. In the lead-up to the 2012 contests, there were only two online pollsters producing about a fifth of all national polling.
At the state level, there is even less of a historical record for online polling. In 2012, there were no state online primary polls in Iowa or New Hampshire, one in Florida, and two in South Carolina. The evidence from 2012 is just too thin to say much of anything about the likely accuracy of online, state-level primary polls.
One potential explanation is that online polls may be sampling more non-voters. These non-voters may not be paying close attention and may simply select the candidate closest to the top of their mind, which could be Trump because of his heavy media coverage. This top-of-mind phenomenon might also explain why Trump is doing better in phone polls of registered voters than in polls of likely voters.
It’s too early to know which set of polls will prove most accurate, and impossible to know nationally, since there is no national primary against which to measure. When the dust settled in 2012, the phone polls did pretty well in predicting the final margins in the early states where most of the polling is currently happening. The polling world is in a serious state of flux, but nothing appears to have changed so systematically as to suggest phone polls will be way off this time around. But the state contests will give us a good yardstick with which to measure accuracy.
For now, the evidence, both from this year’s polls and from 2012, suggests the Trump bump was smaller than it appeared.
Steve Koczela is the president of the MassINC Polling Group, a subsidiary of MassINC, which publishes CommonWealth.
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No, it was not a mirage. Now look into Bernie’s support.
Full Disclosure: I wrote a book about Trump called Donald Trump: A Culture Of Conflict. It’s on Amazon right now right here: http://www.amazon.com/Donald-Trump-Conflict-Kevin-Hess-ebook/dp/B016PHGQ8Q/.
I think what’s likely going on is that ‘likely primary voters’ oversamples the population that traditionally pays attention to politics and is likely to vote Republican anyway. These are people who candidates such as Ben Carson strongly appeal to. Trump’s appeal is to people who are sick of politics as usual – oversampling the people who aren’t sick of politics as usual aren’t going to have as strong of a historical precedence of actually participating in politics as usual.
Furthermore, as a lifelong Dem voter, I’d never show up on polls that sample likely Rep primary voters. Trump appeals to a lot of non-traditional voters. I predict he will do extremely well (for a Republican) in minority demographics even in the general election.
It’s not really rocket science, but nobody seems to get it right. Trump’s appeal is different and it’s based on a lot of very unusual factors, including his ability to manage conflict, so a lot of the old standard metrics are difficult to use when evaluating his true popularity.
The obvious counter to your line of thinking: are these people actually going to show up to vote in the primaries? Trump, while still near/at the top, has lost the momentum he once had. Can he keep his supporters interested enough over the next ~100 days? That, IMHO, is his biggest weakness. Likely voters are reliable, trump voters are historically not.
I agree that Trump will need to push a strong GOTV campaign in the rest of this election cycle. He’s mobilizing forces to do so right now, but his eventual success depends on a good execution on this matter.
Yeah but you forget that Hillary Nixon Clinton, should she win the nomination, will be in Prison by then……….