Kamala Harris is smashing fundraising records as the Democratic Party’s donors — big and small — open their wallets for the vice president in the immediate aftermath of President Joe Biden’s stunning decision to step aside.

In total, Ms Harris’ team raised more than 81 million dollars (£63 million) in the 24-hour period since Mr Biden’s announcement, campaign spokesperson Kevin Munoz said.

The massive haul, which includes money raised across the campaign, the Democratic National Committee and joint fundraising committees, represents the largest 24-hour sum reported by either side in the 2024 campaign.

Ms Harris’ campaign said it was the largest single-day total in US history.

“The historic outpouring of support for Vice President Harris represents exactly the kind of grassroots energy and enthusiasm that wins elections,” Mr Munoz said.

Hours earlier, Future Forward, the largest super PAC in Democratic politics, announced it had secured 150 million dollars in commitments over the same period from donors who were “previously stalled, uncertain or uncommitted,” a senior adviser said.

Taken together, the fundraising explosion puts Ms Harris in a dominant position to secure the Democratic Party’s formal presidential nomination at next month’s national convention — if not sooner.

The donor class’s embrace comes as she locks up endorsements from the vast majority of Democratic governors and members of Congress.

The huge haul also ensures that Ms Harris and her allies can compete with Donald Trump, who has generated stunning fundraising totals of his own in recent weeks as he fights to return to the White House following multiple felony convictions and an assassination attempt.

“This is the next generation people have been waiting for,” Michael Kempner, a member of Mr Biden’s national finance team, said of Ms Harris’ emergence.

“The donors I’ve spoken to are enthusiastic about supporting her. And even those that may have preferred an open convention have quickly coalesced around her overnight.”

Ms Harris has also won the backing of more than two-thirds of the Democratic delegates she needs to become her party’s nominee.

Aiming to put weeks of intraparty drama over Mr Biden’s prospects behind them, prominent Democratic elected officials, party leaders and political organisations quickly lined up behind Ms Harris.

Worries over Mr Biden’s fitness for office were replaced by fresh signs of unity after a seismic shift to the presidential contest that upended both major political parties’ carefully honed plans for the 2024 race.

Speaking to campaign staff in Wilmington, Delaware, Ms Harris acknowledged the “rollercoaster” of the last several weeks, but expressed confidence in her new campaign team.

“It is my intention to go out and earn this nomination and to win,” she said. She promised to “unite our Democratic party, to unite our nation, and to win this election.”

She quickly leaned into the themes that will be prominent in her campaign against Donald Trump over the coming 100 days, contrasting her time as a prosecutor with Trump’s felony convictions — “I know Donald Trump’s type,” she said — and casting herself as a defender of economic opportunity and abortion access.

“Our fight for the future is also a fight for freedoms,” she said. “The baton is in our hands.”

The president called into the meeting from his home in Rehoboth Beach, Delaware, where he is recovering from Covid-19, to lend his support to Ms Harris. He planned to talk about his decision to step aside in an address to the nation later this week.

“The name has changed at the top of the ticket, but the mission hasn’t changed at all,” Mr Biden said in his first public remarks since announcing his decision to step aside, promising he was “not going anywhere” and plans to campaign on Ms Harris’s behalf.

Mr Biden said of his decision to step aside: “It was the right thing to do.”

As he handed off the mantle of leadership to Ms Harris, Mr Biden added: “I’m watching you kid. I love you.”

Mr Biden’s departure freed his delegates to vote for whomever they choose at next month’s convention. And Ms Harris, whom Biden Mr backed after ending his candidacy, was working to quickly secure support from a majority.

Big-name Harris endorsements on Monday, including from governors Wes Moore of Maryland, Gretchen Whitmer of Michigan, JB Pritzker of Illinois and Andy Beshear of Kentucky, left a vanishing list of potential rivals.

House Speaker Emerita Nancy Pelosi, who had been one of the notable holdouts, initially encouraging a primary to strengthen the eventual nominee, said she was lending her “enthusiastic support” to Ms Harris’s effort to lead the party.

More than 1,300 pledged delegates have told The Associated Press or announced that they plan to support Ms Harris at the convention — more than half the 1,976 benchmark set by Democratic National Committee rules.