As they say … garbage in, garbage out.

President Biden called supporters of former President Donald Trump human garbage on Tuesday, potentially blunting an issue Democrats had been repeatedly bringing up in recent days.

Mr. Biden made the comments about Mr. Trump’s backers during a conference call for the campaign of Vice President Kamala Harris organized by the Hispanic advocacy group Voto Latino.

He raged against comedian Tony Hinchcliffe’s now-notorious joke: “Just the other day, a speaker at his rally called Puerto Rico a floating island of garbage,” Mr. Biden said.

“The only garbage I see floating out there is his supporters,” he said, according to video posted by Fox News.

A White House spokesperson, the New York Post reported, said that Mr. Biden, 81, only was referring to Mr. Hinchcliffe.

Mr. Biden quickly tried to backtrack after an uproar from Republicans, who accused him of stoking hatred toward Mr. Trump, the target of two would-be assassins since July.

“Earlier today I referred to the hateful rhetoric about Puerto Rico spewed by Trump’s supporter at his Madison Square Garden rally as garbage — which is the only word I can think of to describe it. His demonization of Latinos is unconscionable. That’s all I meant to say,” he wrote on X.

Those explanations were belied by the actual noun Mr. Biden used — the plural “supporters.”

And Republicans weren’t buying it.

“This is disgusting. Kamala Harris and her boss Joe Biden are attacking half of the country. There’s no excuse for this. I hope Americans reject it,” Republican vice presidential candidate J.D. Vance wrote on X.

Sen. Marco Rubio, Florida Republican and a Cuban-American, brought up the comments at a Tuesday evening rally with Mr. Trump in Allentown, Pennsylvania.

“He’s talking about everyday Americans who love their country and want to dream big again and support you, Mr. President,” Mr. Rubio said, addressing Mr. Trump. “I hope [the Harris] campaign is about to apologize for what Joe Biden just said.”

“We are not garbage. We are patriots. We love America. Thank you for running,” Mr. Rubio said, to which Mr. Trump simply replied, “Wow. That’s terrible.”

Rep. Wesley Hunt, Texas Republican, noted that “the sitting Democratic President of the United States just called Trump supporters ’garbage.’”

“After two failed assassination attempts against Trump followed by the DNC state run media lecturing Republicans to ‘tone down the rhetoric,’ Joe Biden calls tens of millions of Americans garbage. Firing this administration is a moral imperative,” he wrote on X.

Donald Trump Jr. noted that the “media spent all week crying about a joke from a comedian.”

“Meanwhile, Tim Walz called Trump supporters Nazis. Kamala Harris refused to condemn it,” he wrote on X. “And now Kamala’s biggest Democrat ally, Joe Biden, is calling all Trump supporters ‘garbage.’ Absolutely disgusting!!!”

Former Republican presidential candidate Vivek Ramaswamy had another explanation, though.

“You may think it’s his cognitive impairment, but it smells more like an ingenious way to inflict long-overdue revenge on Kamala. Not a bad October surprise,” Mr. Ramaswamy said on X.

• Valerie Richardson contributed to this report.