Just over a year after launching his historic campaign for the White House, Pete Buttigieg on Sunday announced the suspension of his presidential campaign, saying that the best way to advance his campaign’s goal of defeating Donald Trump “is to step aside and help bring our party and our country together.”

“By every historical measure, we were never supposed to get anywhere at all,” the former South Bend, Indiana, mayor said to a cheering crowd of supporters Sunday night, before turning to the still-unseen impact of his historic candidacy.

“We send a message to every kid out there wondering if whatever marks them out as different means they are somehow destined to be less than,” Buttigieg said. “To see that someone who once felt that exact same way can become a leading American presidential candidate with his husband by his side.”

For many LGBTQ advocates, Buttigieg’s run served as a historical counterpoint to the notion that Americans would never vote for a gay president — and a sign that many more LGBTQ candidates would seek elected office.

Roberta Kaplan, the attorney who defended lesbian widow Edie Windsor in United States v. Windsor, the landmark Supreme Court case that gutted the Defense of Marriage Act in 2013, found that there was much to marvel at in Buttigieg’s run.

“If you had asked me after we won the Windsor case seven years ago whether I thought an openly [gay] candidate could credibly run for president in 2020, I would have said you were nuts,” Kaplan tweeted.

If you had asked me after we won the Windsor case seven years ago whether I thought an openly candidate could credibly run for president in 2020, I would have said you were nuts. https://t.co/GfNzURxmfz — Robbie Kaplan (@kaplanrobbie) March 1, 2020

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Sarah Kate Ellis, president and CEO of national LGBTQQ advocacy group GLAAD, said Buttigieg’s historic campaign “showed the world that Americans are ready to accept and embrace qualified LGBTQ public leaders.”

“His candidacy came after decades of LGBTQ Americans fighting to be heard, be visible, and have a place in the American experience," Ellis said. "Pete’s success will no doubt lead to more LGBTQ candidates in political races large and small."

Alphonso David, president of the Human Rights Campaign, the country's largest LGBTQ rights group, praised Buttigieg for a run that centered around “his ideas, not his sexual orientation.”

“History will remember him for never backing down from a fight and never settling for less,” David said.

Tim Miller, a gay former Republican who was “shocked” by Pete’s improbable run, said he was “sad to see him go.”

“I hear from a lot of closeted young gays, I presume because I’m a visible Republican-type, and his campaign really had an impact on them,” Miller told NBC News.

“I think it also shows that we aren’t all the way there,” Miller continued. “Had Pete been straight or older, we may have seen more of the consolidation around him after Iowa that Biden is getting today.”

An NBC News THINK op-ed by Joe Cabosky, a journalism professor at University of North Carolina at Chapel Hill, argued that polls showing 76 percent of Americans open to voting for a gay president were in fact a sign of Buttigieg's uphill battle: He couldn't earn the votes of 24 percent of Americans just because of his sexuality.

For former Houston Mayor Annise Parker, now the president and CEO of the Victory Fund, an LGBTQ organization dedicated to training and electing LGBTQ political candidates, Buttigieg's strong run for president marked a high point in the organization's political activism and a "revolution" in American politics.

"We do not do policy, we do not do allies — we only support LGBTQ individuals," Parker said Monday.

And even then, Victory does not endorse just any LGBTQ office seeker. The candidate has to have a path to victory. Buttigieg, the first viable LGBTQ presidential candidate, was Victory's first-ever presidential endorsement.

"We didn't endorse Pete when he put his exploratory committee together, we didn't endorse Pete when he formally entered the race," Parker said. "We didn't endorse Pete until six months after he started down this path, and by then he had demonstrated over and over again his viability."

For Victory Fund's "back bench" — candidates or elected officials in lower offices or those who seek to run for office one day — there has been a noticeable "Pete effect," Parker said.

"When our candidates see that, they think, 'He can do it, I can do it, too,'" she said.

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