But the moment when the candidate and his husband knew that Pete had made history was on Tuesday. They were together backstage at an early evening event in Laconia, N.H. Buttigieg was waiting to go on stage when the Iowa Democratic Party released the bulk of the caucus results, which now show Buttigieg with a one-delegate lead over Bernie Sanders.

“I remember him saying,” Buttigieg told me, “just to stop and think about what this would mean to so many kids that are peeking out of the closet door.”

This was not a story that Buttigieg offered up, but one I had to coax out of him. He likes to say that he’s “not running to be the gay president of the United States,” but rather “to be a president for everybody.” Several packed days on the campaign trail in New Hampshire have featured only a few moments when the history-making nature of his Iowa victory has shone through, most notably when he choked up during a town hall on CNN discussing how his candidacy might affect "a kid somewhere in a community wondering if he belongs, or she belongs, or they belong, in their own family.”

But for the most part, the historical impact of a gay man winning Iowa has been something that has been thrust upon Buttigieg — by the media, by proud gay activists, by Chasten in that moment backstage — rather than something that he has boasted about.

In recent years there have been vastly different approaches to identity politics in the Democratic Party. Some candidates, like Barack Obama in 2008, have played down their race or gender or sexual orientation, knowing the media and voters who cared about it would play it up. Others have run definitionally as rooted in a specific minority community. The pattern has been that the first to have a realistic shot at breaking a barrier is more circumspect. Obama’s careful campaign, which was the first to have to test the country’s tolerance for a non-white president, frequently feared playing into racist stereotypes, especially about angry black men.

The African-American Democrats who ran this year, while by no means running narrow campaigns that only attempted to appeal to black voters, were less inhibited. Hillary Clinton’s first presidential campaign was less willing to emphasize her gender than her second. Four years after she won her party’s presidential nomination, female presidential candidates were unselfconsciously and proudly feminist.

Pete Buttigieg addresses the rally in Keene. | Emilio Madrid

Buttigieg is in the complicated space of being a barrier breaker: He’s willing to celebrate and ruminate on the history when pressed, but being defined as a gay candidate is not part of his strategy to win.

When I first asked him if he’d thought much about it, he pivoted to familiar talking points about the race. “No, not really,” he said. “You know, we're very focused on the road ahead now and we’re in New Hampshire, it's a state that thinks for itself and doesn't want to be told what to do by Iowa or anyone else. So really we’ve just been keeping our heads down.”

Almost nobody predicted that Buttigieg would win Iowa. He was a distant third in polling averages and the conventional wisdom held that other campaigns, like Elizabeth Warren’s, had superior organizations. In hindsight perhaps it’s on the nose that the McKinsey guy would be the one to master caucus math. His campaign has frequently been compared to Obama’s and he relied on some of the same advisers who steered Obama’s caucus win with a relentless focus on unity and shared values, a gauzy concept that is often mocked by Buttigieg’s online detractors.

“Honestly,” he said, “I think it was mainly the vision that we're putting forward: this idea that we need to turn the page, that the answers are gonna come from outside Washington, that we needed to reach out to everybody who will have to be part of that majority that will defeat Donald Trump, in rural areas, suburban areas, urban areas, and calling everybody into that vision. Of course it helped a lot that we were able to build a formidable ground organization that I don’t think everybody saw coming.”

In New Hampshire, people see it coming. But even if he wins here, Buttigieg is unlikely to be rewarded with the quick consolidation of his party around him in the same way that Al Gore in 2000 and John Kerry in 2004 — two campaigns that knocked out their opponents by winning Iowa and New Hampshire — did. Those candidates had little to prove among non-white constituencies, but Buttigieg still faces deep skepticism.

Even he hesitated when I asked if he should be declared the presumptive nominee if he wins New Hampshire. “I think there's a long way to go,” he said, “and we're gonna keep our heads down and maintain our underdog mentality no matter what. But of course it'll be a great wind at our back.”

If he makes the turn into South Carolina with a pair of victories, or strong showings, he will be facing an unprecedented situation in which the early — overwhelmingly white — states picked the Democratic candidate who is the least popular among black voters, the most important demographic in the primaries.

Joe Biden, who is relying on limping into South Carolina with support from black voters intact, has been pillorying Buttigieg over his record on race. Buttigieg said he had a simple message to overcome the doubts, one that will be buoyed by the results in Iowa and (perhaps) New Hampshire by then: a relentless focus on electability.

“When I'm thinking about black voters in South Carolina,” he said, “I think a lot of that too is about wanting to know that we're putting together a campaign that can win. Nobody's feeling the pain of living under this president more than Americans of color. So many voters I talk to make clear that their top priority is defeating Donald Trump, and I think we have to demonstrate that. Doing well here is of course part of proving that and that gets us another look with a lot of voters. When they take that other look I want them to know that they're seen in my campaign, that we're reaching out and that it's very important to me to build not just a campaign but an American future that is empowering everyone and that has a place for everyone.”

Buttigieg’s rise is absurdly improbable. He has proven a lot of skeptics wrong and his theory of completely changing the psychology of voters in South Carolina by winning Iowa and New Hampshire can’t be dismissed. “We're now in the process of show versus tell,” he said.

At an event late in the day Saturday in Manchester, I ran into Andy Frank, one of Buttigieg’s fellow students at Harvard who was a year behind him (class of 2005). Frank had been in Iowa as an organizer for his old friend and saw the Buttigieg machine spring into action on caucus day and master the convoluted process.

“He always does his homework,“ Frank said. “He breaks down a problem and solves it.”

