The FiveThirtyEight Team Goes To Iowa

DES MOINES — The Iowa caucuses seem so close that I can almost taste them. Yet our FiveThirtyEight Iowa forecasts suggest that a lot of movement can happen between the polls taken now (19 days out) and the results on caucus night. We don’t need to look far back to see how much the numbers can move. The 2012 Republican race changed tremendously in the final 30 days of the Iowa campaign. In an average of polls completed 22 to 31 days before the caucuses (equivalent to surveys taken from Jan. 1 to Jan. 10 of 2016), the average candidate saw his or her support change by 6 percentage points. Much of that had to do with religious conservatives getting behind Rick Santorum, who climbed to 24.5 percent from 5.3 percent in that final month — in part because he gained a pivotal endorsement from social conservative leader Bob Vander Plaats. Many of those Santorum voters left Newt Gingrich, who fell to 13.3 percent from 28.9 percent over that period. It wasn’t just the socially conservative Iowa voters who were changing their tune in 2012. Mitt Romney went to 24.5 percent from 17.2 percent in the final month and ended up basically tied with Santorum for victory in the caucuses. Ron Paul came in a fairly close third place after rising to 21.4 percent from 15.8 percent. The point is that we still have time for a major shift in the campaign. The Des Moines Register poll conducted by Ann Selzer that came out today was completed 22 days before the vote, and it will not be the final word.

We’re still piloting our elections podcast (official launch very soon!) and figured we’d keep it up while in Iowa this week. There’s a strange phenomenon in the early voting states where the political news is being made on the ground, but of course being filtered through media and polling taking place elsewhere. Nate, Clare, Harry and I chatted about the latest polling, how it’s being cited or ignored by the candidates we’ve seen, and our other observations about the pre-caucus politicking. Nate also gives a pretty solid breakdown of the new primary forecast we launched this week. Take a listen below or in the feed for our podcast What’s The Point.

Like so much else at this point in the campaign, Wednesday morning’s Des Moines Register/Bloomberg Politics Iowa poll could be looked at in either of two ways for the leading candidates. For Ted Cruz, the glass-half-full interpretation is that the best poll in the state still shows him ahead — by 3 points over Donald Trump — when several other recent polls in Iowa had shown a narrow advantage for Trump instead. The glass-half-empty interpretation is that Cruz’s lead is diminished: The previous DMR/Bloomberg poll, taken a month ago, had Cruz ahead by 10 points instead. I’m not sure which case I find more persuasive, but here’s a fuller breakdown of the arguments.