For the second time this year, South Bend, Indiana, Mayor Pete Buttigieg is having a moment. Since the October debate, when he took on Sen. Elizabeth Warren on health care and other issues, he has ticked up by a couple points in the national polling averages. He’s also broken into double digits in the last few New Hampshire polls.

But the epicenter of the new Buttigieg bump is in Iowa. He began gaining ground in polls there even before the October debate — his ascent ignited, perhaps, by an aggressive television ad campaign. (Since Sept. 7, Buttigieg’s campaign has aired 3,841 spots for an estimated $2.1 million in Iowa’s broadcast media markets.) And now, if you average every Iowa poll conducted entirely since the last debate on Oct. 15, Buttigieg is right in the thick of a four-way pile-up in the Hawkeye State — in second behind Warren at 19 percent.

Buttigieg is in the hunt in Iowa Polls of the Iowa Democratic caucuses for the four leading Democratic presidential candidates since the fourth debate on Oct. 15 Dates Pollster Sample Warren Buttigieg Biden Sanders Nov. 8-13 Selzer & Co. 500 LV 16% 25% 15% 15% Nov. 6-13 YouGov 856 LV 18 21 22 22 Nov. 7-11 Monmouth 451 LV 18 22 19 13 Oct. 28-Nov. 10 University of Iowa 465 LV 23 16 15 18 Nov. 5-6 Public Policy Polling* 715 LV 21 20 13 14 Oct. 30-Nov. 5 Quinnipiac 698 LV 20 19 15 17 Oct. 25-30 Siena/NYT Upshot 439 LV 22 18 17 19 Oct. 18-22 Civiqs 598 LV 28 20 12 18 Oct. 16-18 Suffolk 500 LV 17 13 18 9 Average 20 19 16 16 *Poll sponsored by a partisan organization. Source: Polls

But the most dramatic example of the Buttigieg Bump 2.0 came just this past weekend, when a new Des Moines Register/CNN/Mediacom poll conducted by Selzer and Co. found Buttigieg now enjoys the support of 25 percent of likely Iowa caucusgoers — a 16-point surge from the consortium’s last Iowa poll in September. He leads Warren (16 percent), former Vice President Joe Biden (15 percent) and Sen. Bernie Sanders (15 percent) by more than the poll’s margin of error. This poll got me wondering: What does a world in which “Mayor Pete” wins the Iowa caucuses look like?

So let’s play a little game. Let’s pretend for a moment that Buttigieg has continued to climb and these Selzer numbers are an accurate picture of the final Iowa results. How would it scramble the race?

What could happen in New Hampshire

It’s the morning of Feb. 4, 2020, and fresh copies of the Union Leader blare from every newsstand in New Hampshire: “BUTTIGIEG SURGES TO WIN IOWA.” But how much would that actually matter in the Granite State? History tells us anywhere from “not at all” to “a fair bit.” The extent to which winning Iowa bolsters a candidate’s numbers in New Hampshire is actually pretty inconsistent; in 2016, for instance, Iowa winners Ted Cruz and Hillary Clinton did no better in New Hampshire than their pre-Iowa polls suggested. So one scenario is that Buttigieg, and the other candidates, stay more or less at their pre-Iowa levels of support in New Hampshire, which would lead Buttigieg to a disappointing fourth-place finish based on the current polling average there.

Buttigieg isn’t as strong in New Hampshire Polls of the New Hampshire Democratic primary for the four leading Democratic presidential candidates since the fourth debate on Oct. 15 Dates Pollster Sample Warren Biden Sanders Buttigieg Nov. 6-13 YouGov 535 LV 31% 22% 20% 16% Nov. 6-10 Quinnipiac 1134 LV 16 20 14 15 Oct. 21-27 UNH 574 LV 18 15 21 10 Average 22 19 18 14 Source: Polls

Another argument in favor of this scenario is that none of Biden, Sanders or Warren would have truly bombed in Iowa if the results of the Selzer poll came true; they’d each be able to claim that they were part of a three-way tie for second place. Furthermore, all four of them would still have met or exceeded 15 percent of the vote statewide in Iowa, meaning all four would qualify for some of the state’s 41 pledged delegates, which you must receive at least 15 percent to do. That could portend an unprecedented open race — and make a brokered convention a real possibility, as no more than three candidates have ever earned more than 15 percent of the vote in any state or territory’s caucus since the 15 percent threshold was established in 1992.

But there is also a very plausible scenario where Buttigieg does surge in New Hampshire. For starters, the state should be fertile ground for him demographically: Like Iowa, its Democratic primary electorate is relatively old, white and college-educated, three groups with whom Buttigieg does disproportionately well in national polls. And while the average “bounce” for the Iowa winner varies from cycle to cycle, FiveThirtyEight editor-in-chief Nate Silver found in 2011 that, on average, Iowa winners through 2008 got a 7-percentage-point bounce in New Hampshire. But of course, these bounces aren’t uniform; candidates who outperform expectations in Iowa tend to get more of a boost. So if our hypothetical holds true and Buttigieg wins Iowa with a vote share that’s almost 20 points higher than he is polling nationally, it’s easy to imagine him closing his 8-point deficit in the New Hampshire polling average from the table above — especially if he steals support from the other three front-runners in the process.

Who might be hurt most by this scenario? Well, it could unfold a number of different ways, but my prior is that Warren would have the most to lose. Between her, Biden and Sanders, she lost the most ground amid Buttigieg’s gains in the Selzer poll, which could be because she and Buttigieg have similar bases — college-educated whites. And while Warren has so far dominated Buttigieg among liberal voters, the Selzer poll contained a warning sign for her: Thirty-eight percent of likely caucusgoers said she was too liberal, up from 23 percent in Selzer’s March poll. Yet only 7 percent thought Buttigieg was too liberal; 63 percent thought he was “about right.” If that’s true in Iowa, where 68 percent of 2016 Democratic caucusgoers identified as liberal, it is likely to be true in demographically similar New Hampshire.

But I could also see Biden taking a hit; just as Buttigieg’s rise could threaten Warren’s hold on college-educated whites, it could threaten Biden’s hold on more moderate voters and those concerned about “electability.” For instance, in the Selzer poll, Buttigieg got 29 percent support among voters who said a candidate’s ability to beat President Trump was more important than where he or she stood on the issues. This was more than any other candidate; Biden came in second with only 17 percent.

As for Sanders’s support, I actually think he would be safest in the event of a Buttigieg surge. When asked who their second choice for president is, very few Sanders supporters say Buttigieg. And according to multiple polls, fewer Sanders supporters say they are open to changing their minds than supporters of the other three front-runners. The overall loyalty of Sanders’s voters means he could be in line to get 15-20 percent of the vote in New Hampshire no matter what happens in Iowa, which could be enough to finish second if Buttigieg siphons off support from the other front-runners.

What could happen in Nevada, South Carolina and beyond

The feel of the race could change pretty dramatically after New Hampshire, however, and that’s because the next several states to vote are far less white than the two leadoff hitters. And even as Biden has faltered in polls of Iowa and New Hampshire, he particularly still enjoys healthy leads in Nevada and South Carolina, while Buttigieg has struggled there. This is due in large part to his struggles with nonwhite voters. According to a Telemundo poll from late October, only 2 percent of Hispanic Democrats nationwide supported Buttigieg. And it’s even worse for Buttigieg when you consider that African Americans represent a large share of the electorate in South Carolina and several Super Tuesday states: I found last month that only 2 percent of black Democrats nationwide supported Buttigieg in an average of October polls.

So the big question for phase two of our hypothetical primary is whether Buttigieg can improve his standing among Democrats of color, especially black Democrats. There are some reasons to think he can, but there are also other reasons to think he can’t.

One reason why Buttigieg’s support among black and Hispanic Democrats could grow is that, in general, they tend to identify as less progressive than white Democrats, so they might be more inclined to support Buttigieg than Sanders or Warren if Biden’s candidacy looks weakened after Iowa and New Hampshire. And black voters, at least, are highly aligned with the Democratic establishment; if the party decides Buttigieg is its guy after seeing him win Iowa and New Hampshire, black voters could follow its lead. It wouldn’t be the first time that winning both Iowa and New Hampshire earned a candidate a second look from nonwhite voters; for example, John Kerry had no strong ties to the black community before he won Iowa and New Hampshire in 2004, but he won the black vote handily in subsequent contests.

But Buttigieg also faces challenges that Kerry didn’t. There was no clear front-runner among black voters in 2004 the way Biden is today. And Buttigieg’s mayoral administration has had a strained relationship with South Bend’s black community since demoting the city’s black former police chief and implementing housing policies that critics say disproportionately disadvantaged African Americans. It’s also possible that some black voters will not be comfortable voting for a gay presidential candidate. According to a recent Politico/Morning Consult poll, white voters said that they were “definitely” or “probably” ready for a gay or lesbian president 51 percent to 37 percent, while black voters said they weren’t ready 42 percent to 38 percent.

Since these factors are already baked in, I’m not sure how much Buttigieg’s success in Iowa and potentially New Hampshire will do to make him a viable national candidate (i.e., address his weaknesses among voters who aren’t white). But I do think that the damage done to the other front-runners by a Buttigieg one-two punch in Iowa and New Hampshire could create big problems for their campaigns. To take one example, if Buttigieg winds up pulling disproportionately from Biden supporters in the first two states, it could damage Biden enough in Nevada and South Carolina that another candidate (not necessarily Buttigieg) could inherit his support among nonwhite Democrats.

On the other hand, if Buttigieg winds up pulling disproportionately from Warren, it could make for a more complicated race. A world where Buttigieg wins both Iowa and New Hampshire is one where Warren will have finished second (or worse) in two early states that, on paper, look tailor-made for her. The underwhelming performances could drain her support among two key elements of her base — wonky-but-not-ideological college-educated whites, who could switch to Buttigieg, and devoted progressives, who could switch to Sanders. In fact, the Selzer poll already showed signs that Iowa liberals were leaving Warren for Sanders; if that happens nationwide, the Democratic primary could exit Super Tuesday as a three-way race between Biden as the candidate of nonwhite voters, Buttigieg as the candidate of party elites and Sanders as the candidate of the left.

Of course, we’ll have to wait and see. Buttigieg will have to hang onto the lead in Iowa for almost three months for these scenarios to come true — otherwise, the shifting race could create even newer hypotheticals for us to consider.

CORRECTION (Nov. 19, 2019, 8:31 a.m.): A previous version of this article incorrectly identified the winner of the Republican caucuses in Iowa in 2012. While Mitt Romney claimed a narrow victory on election night, the Republican Party of Iowa eventually declared Rick Santorum the official winner.





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