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The scene from a 2008 Iowa caucus | Photo: Citizensharp / WikiCommons

Your questions, answered.

Q: I wanted to write in and see if you wanted to tackle a question I tried to ask Nate Silver on Twitter yesterday. 538 posted a bunch of polling averages (nationally and for each primary state). One question I asked, as a fan of Mayor Pete, is if there is any data to let us know how voters react after the first few primaries. For example, if Buttigieg wins Iowa, how does that affect those who are identifying as voting for Biden in the polls. Do a significant portion of voters switch from Biden to Buttigieg in New Hampshire and beyond based on the Iowa win?

- Chad, Columbus, OH

Tangle: Voters hear a ton about Iowa and New Hampshire, and with good reason: they’re the first two states to vote in a primary contest and they often set the stage for the rest of the campaign. The “data” that I think answers your question is probably not as niche or complex as you think. After all, we can look back at candidates’ performances in Iowa and New Hampshire and then consider how they did in the presidential race. I’ll start by saying this, though: How winning Iowa impacts later states is hard to tell, mostly because winning Iowa is not an event that happens in a vacuum. When a candidate wins Iowa, they immediately get tons of free media, television appearances, and fundraising (voters typically throw themselves behind people who are viewed as electable). Right before early voting states is also when huge oppo research and attacks on fellow Democrats will heat up, so it could be tough to tie a loss in Iowa to a candidate’s fall in the polls instead of, say, a series of damaging articles that come out around that same time. Still, there’s a lot of data to suggest the emphasis on Iowa and New Hampshire is worthwhile.

For the purpose of this exercise, we’ll just talk about Democrats (though it seems worth noting that no Republican has become a nominee for president without winning Iowa or New Hampshire in 40 years).

Since 1976, over the last 11 elections, seven eventual nominees for president won Iowa, including the last four (Hillary Clinton, Barack Obama, John Kerry and Al Gore). During those same 11 elections, the winner of the New Hampshire primary has produced six nominees. Only one person, Bill Clinton, has gone on to become president without winning Iowa or New Hampshire primaries (and that only happened because an Iowan politician was running, so Clinton didn’t even try to win). In 2004, General Wesley Clark won Oklahoma in the Democratic primary. He was the only candidate since 2000 to win a state that he didn’t have home-court advantage in (i.e. a state where he was born, lived or served) after losing Iowa or New Hampshire. In other words: only one candidate since 2000 who lost both Iowa and New Hampshire went on to successfully campaign and win in a state they weren’t expected to win.

One might contest that Iowa or New Hampshire are predictive, not impactful, and candidates’ success after winning Iowa or New Hampshire just reflects the fact they were popular heading into the election. But the polls have, historically, told a different story. Nate Silver, who you first posed this question to, published data in 2011 that found the winners of Iowa, on average, got a 7-percentage-point bounce in New Hampshire. The bounce is inconsistent, though, and sometimes non-existent. Winning in Iowa also does not necessarily predict victory in New Hampshire, even though the two both have dominant older, white voting blocs. Still, if Buttigieg wins Iowa, as some polls predict he will, it’s quite possible that a victory there would help him close the gap in New Hampshire, too, and leave the first two states with a clean sweep. I’d imagine that there would be a sizable number of older, white Biden voters who would consider jumping ship if Buttigieg won Iowa or New Hampshire or both.

All of this, though, comes with a major caveat: many pollsters and campaign experts think the role Iowa plays in the election will change this year. That’s for two reasons. One, Democrats are increasingly reliant on non-white voters, of which there are few in Iowa and New Hampshire. This simple reality has a lot of people looking to South Carolina, which votes fourth on the primary calendar, as the first major test for Democratic nominees. South Carolina has a huge group of black, Democratic voters who seem to prefer Biden to the field, the same way non-white voters seem to prefer Biden to the field in Nevada (another early voting state).

The second reason Iowa’s role could change is that Iowa could end up having an unprecedented split. Democrats have a very complicated caucus system in Iowa. People attend the caucuses and literally move around a room, standing in sections denoted to the candidates of their choice, all trying to form 15 percent or greater support. If a candidate doesn’t get 15 percent support in a precinct, they’re basically eliminated. Each candidate is vying for some or all of the 41 pledged delegates in Iowa, which are added together at the end of the race to determine the winner. But this year, some polls show Buttigieg, Biden, Warren and Sanders all with more than 15 percent support in Iowa. That’s totally unprecedented, and it could mean more than one candidate walks away from Iowa claiming victory, and could significantly mute the media hype around the winner. Splitting the delegates in Iowa four ways could really reduce the impact of the media’s coverage, the way donations come in, and how the polls move. And right now, that split is looking pretty possible.