Joe Biden drops out of election, upending race for White House

Party sources told the BBC that White House staff were told only moments before the statement was released on Sunday afternoon, although Mr Biden had spoken to Ms Harris beforehand.

Dozens of senior Democrats and party grandees including Barack Obama, the former president, Senate leader Chuck Schumer and former House speaker Nancy Pelosi immediately praised the decision and lauded Mr Biden's accomplishments in office.

However, not all have openly accepted Mr Biden's endorsement of Ms Harris.

Mr Obama stated that he had "extraordinary confidence" that an "outstanding nominee emerges" but did not explicitly back Ms Harris. Ms Pelosi has not commented.

Peter Welch, the first Democratic senator to call on Biden to drop his re-election run, called for an "open process" to nominate Harris.

Former president Bill Clinton and 2016 Democratic candidate for president Hillary Clinton said they backed her as a candidate, saying they would "fight with everything we've got to elect her".

Several of those who could challenge for the nomination also praised Mr Biden - but stopped short of commenting on his endorsement of his vice-president.

Gretchen Whitmer, the governor of Michigan, stated that her job "will remain the same... doing everything I can to elect Democrats and stop Donald Trump."

Gavin Newsom, California's governor, praised Mr Biden as a "selfless" president, but stopped short of further comment on who would succeed him.

Pete Buttigieg, the current transport secretary, said Mr Biden had "earned his place among the best and most consequential presidents in American history". He too did not address the next step for the party.

The Democratic National Committee meanwhile filed to amend the names of its fundraising committees to the Harris Victory Fund and Harris Action Fund.

Two major Democratic donors - LinkedIn co-funder Reid Hoffman and investor Alexander Soros - publicly endorsed Harris.

Mr Hoffman said on X/Twitter that when "presented with the choice between Kamala Harris and Donald Trump, I believe in the American people to make the right decision for our country".

But within an hour of Mr Biden's announcement, the pro-Trump super-PAC campaign fund Make America Great Again posted an advert attacking Mr Harris, claiming "she covered up Joe's obvious mental decline".

Donald Trump added: "Whoever the Left puts up now will just be more of the same."