Iowa’s top pollster shocks race with finding that Harris leads Trump

It’s important to remember this is just one single poll, even if the pollster has an uncanny record of closely predicting her state’s elections. The usual caveats that even the best pollsters get outlier results sometimes or fail to detect a systematic error all still apply. One survey does not suddenly wipe away hundreds of others, including many by well-regarded pollsters in their state and nationally.

That said, there’s a reason the top election analysts were watching to see what Selzer found and I don’t want to be overly dismissive of the results either. While Iowa isn’t a swing state, it has a lot in common demographically with nearby states like Wisconsin and Michigan. Just as Selzer’s 2016 and 2020 polling was considered an indicator that Trump was performing better with midwestern white voters than most swing state pollsters believed, it’s worth taking seriously whether Selzer’s 2024 polling showing the opposite trend is relevant as well.

As analysts like Ron Brownstein have noted, there are recurring signs that Harris is maintaining her support or even outperforming Biden among white voters, including seniors, which has helped her make up for declining support with Black and Latino voters in some polls. It’s also not impossible to find some other regional examples that might bolster the case: Polls in Nebraska, which splits its electoral votes, have shown Harris doing extremely well in the Omaha-based 2nd District. Even if Trump wins Iowa and Selzer ends up being off by 7, 8, or even 9 points, that would still be a zone where (assuming white voters behave similarly elsewhere) Harris might be winning the decisive swing states.

“It’s possible he has a lower margin than 2020, but I just don’t think he can lose Iowa,” David Kochel, a veteran Republican strategist in Iowa tweeted. “This ain’t great news for his Wisconsin effort, though, if he’s slipped a lot here. Very similar electorates.”

There’s another reason to take Selzer’s polling seriously. After underestimating Trump in key states in 2016 and 2020, pollsters have adopted new techniques — like weighting to how respondents say they voted in the last election — in order to try to ensure they’re finding enough Republican support. Selzer, and some other high-quality pollsters like the New York Times/Siena survey, do not employ these methods, arguing they do not have a proven track record of success.

Elections guru Nate Silver has also accused certain pollsters, especially less established ones, of “herding” their results toward a close race using subtle methodological decisions out of fear of getting things wrong in either direction. Whatever you think of Selzer’s latest poll, she’s above suspicion in this regard — a big reason her surveys enjoy such a strong reputation is that they don’t just replicate the conventional wisdom or average survey results of the moment.

Taken together, it would not be crazy if some pollsters found themselves overestimating Trump support this time after bending backwards to not do the same thing for a third cycle in a row. It’s also possible the pollsters taking aggressive steps to find Trump supporters end up correct — or even that they still underestimate him — but Selzer’s record even in years with big polling misses elsewhere is a relevant data point.

I’d add one more wrinkle to the Selzer poll that is different this year. For the first cycle in recent memory, Iowa has definitively not been treated as a swing state by either presidential campaign. Meanwhile, the seven top battleground states have seen billions of dollars in ad spending, constant visits from candidates, and extensive canvassing operations. For that reason, it was my strong personal prior before the Selzer poll dropped to not assume it would be as predictive of other states this time.

That said, the Selzer result is so stunning that it raises an entirely different scenario that does have recent precedent: A presidential campaign failing to notice a state that once seemed safe falling into competition until it’s too late.

In a memo, Trump’s pollsters called the Des Moines Register poll a “clear outlier” and pointed to a separate Iowa poll today by Emerson College that found Trump leading by 10 as more realistic.