Democratic presidential contender Pete Buttigieg’s sexuality has become a campaign issue after a radio host questioned if voters would pick a man “kissing his husband on stage”, a media report said.

On his radio show which is nationally syndicated to millions of listeners, the firebrand conservative host Rush Limbaugh on Wednesday imagined Democrats’ deliberations over who to vote for, the BBC report said on Friday.

“They’re saying, ‘OK, how’s this going to look? Thirty-seven-year-old gay guy kissing his husband on stage, next to Mr Man, Donald Trump’,” the BBC report quoted Limbaugh as saying on the show.

If elected, the former mayor of South Bend, Indiana, would be the first openly gay US President.

Buttigieg did not directly address the radio host’s remarks during an event in Las Vegas, Nevada, on Thursday night, but said: “I’m proud of my marriage. I’m proud of my husband.”

President Trump was asked in a Fox News interview on Thursday if he would be open to voting for a gay candidate, the BBC report said.

“I think so. I think there would be some that wouldn’t, and I wouldn’t be among that group, to be honest with you. I think that it doesn’t seem to be hurting Pete Buttigieg,” he said.

Meanwhile, Democratic contender and former Vice-President Joe Biden, who has been beaten by Buttigieg in the first two votes of the presidential primary season, in Iowa and New Hampshire, lashed out at Limbaugh.

“It is part of the depravity of this administration… Pete and I are competitors, but this guy has honour, he has courage, he’s smart as hell,” the BBC quoted Biden as saying in an ABC interview.

This report came after one voter in the February 3 Iowa caucuses wanted to rescind her ballot for Buttigieg after learning he was gay.

“I don’t want anybody like that in the White House,” she said. “So, can I have my card back?”