As young Democrat Pete Buttigieg emerges as a genuine contender in the 2020 White House race, his rise poses the question of whether America is ready for an openly gay president.
When Buttigieg announced in January that he was considering a presidential run, few had heard of the 37-year-old outside the small Indiana city of South Bend where he is mayor.
Today, he is in the small pack leading the Democratic race, regularly appearing on the campaign trail with husband Chasten Buttigieg -- a junior high school teacher who now stands to become the first-ever US first gentleman.
"Mayor Pete" -- as he likes to be known -- has drawn a surge of fundraising, and over the weekend topped a poll in Iowa, which votes first in the Democratic nominating contest.
The latest national polls put the Afghanistan veteran fourth behind a trio of septuagenarians vastly more experienced than he is: fellow centrist former vice president Joe Biden, and the progressive senators Elizabeth Warren and Bernie Sanders.
Buttigieg claims to have revived South Bend, an industrial city of 100,000 residents, and wants to end the "horror show" that he says is the presidency of Donald Trump.
While Buttigieg does not dwell on his sexual orientation, he has spoken candidly about his decision to come out four years ago, and his engagement in 2017 to Chasten -- with whom he hopes to start a family, perhaps even in the White House.
Unlike Europe where half a dozen countries have elected gay leaders since 2009, the barrier to LGBT presidential candidates, as well as women, remains unbroken in the United States.
Barack Obama, the first black man elected president in 2008, was preceded in the White House by 43 white males, none openly gay.
But in recent years and especially since the legalisation of same-sex marriage in 2015, "the landscape for LGBTQ candidates has shifted dramatically," said Annise Parker, president of the Victory Fund, an organisation that supports gay candidates in the United States.
"When I was elected I was the first and only LGBT mayor in the top 100 (cities)," recalls Parker, who was mayor of Houston from 2010 to 2016.
"Now we have three (as well as) two governors, two US senators. The number of out politicians at the highest level is increasing very rapidly," she added.
The first openly gay presidential candidate was Fred Karger, who sought the Republican nomination in 2012, although his candidacy never took off.
On its website, Victory Fund regularly updates a map of elected LBGTQ officials in the United States: the number currently stands at 762 across all levels of government and all states except South Dakota and Mississippi.
Recent national polls have suggested voters are more open to LGBTQ candidates.
In May, a Gallup poll found 76 percent of respondents said they would vote for a gay candidate, three times more than in 1978.
Among Democrats, who are often more concerned with minority rights, the share rose to 83 percent.
John Della Volpe, who studies voter behavior at the Harvard Institute of Politics, said most of the 2020 electorate, especially young voters, do not care about sexual orientation.
"The attributes that voters are looking for are integrity, vision, authenticity, life experience," he told AFP. "The stakes are just too high to even focus on age, race, gender, sexual identity."
In terms of integrity and authenticity, being openly gay is a "strength," Volpe believes, adding that Buttigieg's story about being "a young person struggling with their identity" rings true.
But reluctance remains.
A poll released last month found that 45 percent of those questioned thought America was not, or probably not ready for a gay president.
Interviews conducted in July with a sample of black Democratic voters in North Carolina found some were uncomfortable with Buttigieg's sexual orientation, according to a campaign team memo leaked to the media.
Most, however, were able to overcome their reservations after hearing him speak in calm and measured tones and once he had reminded them he is a practicing Christian, the memo added.
In a hyper-polarised country where Democrats want the best candidate to unseat Trump, fears that Buttigieg's sexual orientation could be a handicap may work against him.
T.J. Thran, 25, said this month at a Buttigieg rally in New Hampshire he worries the candidate's sexuality might turn off some working-class voters.
But LGBTQ activists say even if he doesn't win the candidacy, his run will leave a lasting legacy.
"He is already breaking barriers," said Parker.
"What he has been doing very well is showing how completely American he is and how completely transparent he is about his relationship with his husband.
"That is changing the landscape for everybody else who will be running after him," she added.