Firebrand conservative Rush Limbaugh said Democrats must realise America is still not ready to elect a gay man.
Mr Buttigieg's Democratic rivals leapt to his defence, and President Donald Trump said he would vote for a gay man.
Mr Limbaugh was last week awarded a top civilian honour by the president.
On his radio show which is nationally syndicated to millions of listeners, Mr Limbaugh on Wednesday imagined Demcorats' deliberations over who to vote for.
He said: "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.'" » | Valentine’s Day, 2020
Sorry, Fossils! America needs a gay president. It will awaken the nation to the realities of the twenty-first century. Go for it, Pete! Your country needs you! – Mark
