Democrats warn JD Vance will enable Trump’s ‘extreme Maga agenda’

Democrats were quick to seize on Donald Trump’s decision to name as his running mate JD Vance, the hard-right Ohio senator whose past opposition to the former president and Republican nominee included calling him “America’s Hitler” but who now supports Trump with fiery populist rhetoric.

Related: Donald Trump names JD Vance, formerly one of his fiercest critics, as 2024 running mate

A Democratic party statement said: “Vance is an ultra-Maga extremist who’s ready to help Trump pass his Project 2025 agenda. Stop Trump-Vance. Vote Biden-Harris.”

Vance has praised Project 2025, a far-right blueprint for a second Trump term. Trump has tried to distance himself from the effort, which is co-ordinated by the Heritage Foundation. Democrats want to tie him to it.

Joe Biden’s campaign warned that Vance should not be trusted to put country over party, as Mike Pence did as vice-president when, on 6 January 2021, he refused to do as Trump demanded and block certification of Biden’s election win.

“Trump picked JD Vance as his running mate because he will do what Mike Pence wouldn’t on January 6: bend over backwards to enable Trump and his extreme Maga agenda, even if it means breaking the law and certainly no matter the harm to the American people,” Jen O’Malley Dillon, Biden’s campaign manager, told reporters.

On the same call, officials and surrogates highlighted Vance’s anti-choice record on abortion, accusing him of wanting to “take women back decades”.

The Massachusetts senator Elizabeth Warren said Vance was a faux populist whose nomination was “great news for the wealthiest Americans and lousy news for everyone else”.

“Billionaires on Wall Street and Silicon Valley are cheering but there is no joy for working people,” Warren said.

Elsewhere, Robert Garcia, a California congressman, called Vance “an extremist with views that are completely outside the mainstream” and said: “The fact that he immediately politicised the assassination attempt against former President Trump and blamed Democrats is shameful. There couldn’t be a more irresponsible pick.”

On Saturday, at a rally in Pennsylvania, Trump was shot in the ear. One person was killed and two injured. In the immediate aftermath of the shooting, Vance claimed Democratic campaign rhetoric “led directly to President Trump’s attempted assassination”.

The gunman’s motive has not been determined.

Monday’s Biden campaign call marked something of a return to normal, after a pause in negative advertising. Officials said the contrast between the Trump-Vance ticket and Biden-Harris was clear.

O’Malley Dillon said: “With Trump and Vance now entering the general election, they’re facing off against the Biden-Harris ticket, and I will certainly take that matchup any day of the week – and twice on Sunday.”

Eager to turn the page on party turmoil set in motion by Biden’s disastrous debate display last month, the campaign said it had committed to a vice-presidential debate, now a televised showdown between Harris and Vance.

“She is strong. She knows what she’s talking about and she doesn’t give an inch,” Warren said of Harris. “I’m looking forward to this debate.”

Other Democrats highlighted Vance’s far-right views.

Ayanna Pressley, a Massachusetts representative and member of the high-profile “squad” of House progressives, pointed to Vance’s opposition to abortion ban exceptions for rape and incest.

“JD Vance has told us who he is,” Pressley said. “Believe him.”

Young Democrats of America, a campaign group, said Vance’s “radical attacks on the LGBTQ+ community, Bipoc Americans, and reproductive healthcare are only getting started.”

The Biden campaign pointed to remarks in which Vance called no-fault divorce “one of the great tricks that I think the sexual revolution pulled on the American populace”, because it allowed people to “shift spouses like they change their underwear”.

“JD Vance says women should stay in violent marriages ‘for the sake of their kids’,” a campaign tweet said.

Before entering politics, Vance was a “public affairs” marine turned venture capitalist and bestselling author, having written Hillbilly Elegy, about his upbringing in poverty-stricken Ohio.

The book was widely seen as an important portrait of the kind of area likely to back Trump. But in 2015 and 2016, as Trump surged to the presidency, Vance came out against him and on Monday, many reached for examples of such anti-Trump statements.

Shannon Watts, a leading campaigner for gun reform, was one of many to point to Vance’s description of Trump as “America’s Hitler”.

In February 2016, in a message to a friend, Vance said: “I go back and forth between thinking Trump is a cynical asshole like Nixon who wouldn’t be that bad (and might even prove useful) or that he’s America’s Hitler. How’s that for discouraging?”

Nicholas Thompson, chief executive of the Atlantic, pointed to a piece from the same year in which Vance wrote, under the headline Opioid of the Masses: “To every complex problem, Trump promises a simple solution … He never offers details for how these plans will work, because he can’t.

“Trump’s promises are the needle in America’s collective vein.”

Vance recently told Fox News that back then, he “didn’t think [Trump] was going to be a good president. He was a great president. And it’s one of the reasons why I’m working so hard to make sure he gets a second term”.

Having won Trump’s trust, notably by supporting his election fraud lie, Vance won a US Senate seat in Ohio in 2022.

His elevation as Trump’s running mate also came after he overcame Trump’s reported aversion to beards. Nonetheless, it prompted predictions of tricky moments to come.

Anthony Michael Kreis, a constitutional law professor at Georgia State University, said: “JD Vance has said so many awful things about Donald Trump on tape, it’s going to be looped over and over and over again in every swing state.”