Joe Biden has decided to stand down in the race for US President after weeks of damaging revelations about his mental fitness.
The 81-year-old tried to bat away calls to quit the race, insisting he was the only person who could defeat Donald Trump.
But donors, party members and bigwigs finally forced him to withdraw his candidacy.
The calls for Biden to stand aside escalated from his disastrous debate with Trump on June 27, in which he repeatedly lost his train of thought.
There is no precedent in modern US history for a presidential nominee to drop out this close to an election.
The selection of Biden’s replacement will be confirmed at the Democrat National Convention, which this year begins on August 19.
Delegates to the convention anoint the party’s candidate at a formal vote.
It is also possible that the selection could take place in a roll-call vote in a virtual event weeks before the election.
As Biden swept the Democrat primary, in which he faced only a minor challenge from Congressman Dean Phillips, he won almost 3900 of the party’s 4000 delegates.
Under the Democratic rule book, those delegates are expected to “reflect the sentiment of those who elected them”.
Biden’s endorsement of Kamala Harris may mean many feel they should follow his lead.
However, the delegates are now free to vote as they choose and those delegates could decide an alternative candidate is better placed.
Harris will need support from party bigwigs as well as the other names being floated as potential candidates to secure the nominations.
Gretchen Whitmer, the governor of Michigan, and Gavin Newsom have been touted as alternatives.
They expressed support for Biden following his disastrous debate and may feel that putting themselves forward is unwise.
Harris’ team has briefed that they would forcefully object if a white candidate was promoted over her head, ignoring her position as the first ever black woman to be sworn in as vice president.
If any other Democrat feels they have a better shot than Harris – and she polls worse than several other potential candidates in match-ups against Trump – they would need to secure the signatures of 600 delegates. This would mean they are “nominated” as a potential candidate.
They would then compete with Harris to secure a majority of the roughly 4000 delegates in the first ballot.
If several candidates secure a nomination but none receive a majority that would herald a “brokered convention”. In this, delegates can vote for anyone who puts their name forward in as many rounds of voting as it takes to secure a candidate.
The last brokered convention was in 1952. Illinois Governor Adlai Stevenson, who had repeatedly said he did not want to run, opened the event with a witty speech. When there was no clear winner after the first ballot, he put his hat in the ring. Having secured the nomination, Republican Dwight D. Eisenhower defeated him in the national vote.
The Biden-Harris campaign has around US$91 million ($151m) of cash on hand, according to documents filed on May 31.
Combined with allied Democratic organisations the re-election effort has access to US$240m – a healthy war chest with which to mount a presidential campaign.
Rob Flaherty, a deputy manager for the Biden campaign, claims that replacing Biden would mean surrendering those funds and that his successor would “go into a general election in the weakest possible position with zero dollars in their bank account”.
However, since their campaign account was registered with the Federal Election Commission in the name of both candidates, Harris would be able to make use of that US$91m.
“Any campaign depository designated by the principal campaign committee of a political party’s candidate for President shall be the campaign depository for that political party’s candidate for the office of Vice President,” according to federal campaign law.
This would not be the case if someone other than Harris replaced Biden, even if she remained on the ticket as a running mate, experts say.
The development would be disastrous for a presidential candidate who had to start fundraising from scratch just months away from election day – particularly when the Trump campaign has finally clicked into gear and closed the long-standing cash gap.
The conservative Heritage Foundation has announced it will sue if the Democrats replace Biden.
A memo drawn up by the think tank suggested that there were certain states where “pre-election litigation” would make his replacement “difficult and perhaps unsuccessful”.
Biden has already been provisionally nominated as a candidate in Washington, which has a deadline of August 20 to get on the ballot.
Theoretically, whoever takes the US President’s spot will have to register before this date – which falls in the middle of the party convention.
Ohio and Alabama had set their ballot deadlines for August 7 and 15. However, both states have now shifted this back, removing at least one hurdle for Biden’s successor.
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