WASHINGTON (AFP) - Mockery of Democratic candidate Pete Buttigieg's homosexuality by a close ally of President Donald Trump drew fire on Friday (Feb 14), pushing the politically sensitive issue higher into the headlines than ever before.
Buttigieg is the first openly gay man with a realistic chance of getting a major party nomination to run for the White House.
So far, the former Indiana small city mayor has rarely had to confront homophobia on the campaign trail, where his husband has often joined him.
But controversy erupted on Wednesday when Rush Limbaugh, a radio host who acts as a kind of spiritual leader of right-wing Republicans, said Democrats would never choose a gay man over Trump.
"They're saying, 'OK, how's this going to look?'" Limbaugh asked.
"Thirty-seven-year-old gay guy kissing his husband on stage, next to Mr Man, Donald Trump'."
Buttigieg is 38.
Bernie Sanders, who is furthest to the left of the Democratic candidates, tweeted on Friday that "personal attacks like this are unacceptable. The homophobic comments from Rush Limbaugh about @PeteButtigieg are outrageous and offensive."
"Together, we will end the division and hate led by Donald Trump," Sanders tweeted.
On Thursday, former vice-president Joe Biden, who is battling with Buttigieg for the support of more centrist Democrats, also defended his rival.
"You saw, you just had on Rush Limbaugh, I mean, my God, it's part of the depravity of this administration," he said on ABC television.
"Pete and I are competitors, but this guy has honour, he has courage, he's smart as hell," Biden said.
As for Trump, he has carefully staked out a middle ground - avoiding anything controversial on Buttigieg, while not denouncing apparent homophobia against him.
Asked on the Geraldo Rivera radio show on Thursday whether Americans could vote for a gay president, Trump said "I think so."
Then he added, "I think there would be some that wouldn't. I wouldn't be among that group, to be honest with you."
"It doesn't seem to be hurting Pete Buttigieg," Trump said.
Trump is so close to Limbaugh that he chose to dramatically award him the Presidential Medal of Freedom - the highest civilian honour in the country - during the State of the Union speech earlier this month.
In doing so, Trump declared that Limbaugh was "beloved by millions of Americans."
Although hugely popular in right-wing circles, Limbaugh has been criticised for years over remarks seen as racist, misogynist and homophobic.