Joe Biden has pulled out of the presidential race - so what happens now? How can he be replaced?
We are in uncharted territory, as no serving president who was due to re-stand as a candidate has ever pulled out at this stage. This is what will happen in the coming weeks.
Tuesday 23 July 2024 14:48, UK
Kamala Harris looks like she may be the next Democratic presidential candidate following Joe Biden's withdrawal from the race. Here's what happens now.
It's an unprecedented situation - no presidential candidate has ever withdrawn so late in the electoral cycle or in the campaign.
Between now and election day the Democrats will need to choose a nominee (Ms Harris is the clear frontrunner at the moment) and a vice presidential candidate, get them on to the ballot and do their best to take the fight to Donald Trump.
Biden's replacement: Is it definitely Kamala Harris?
While initially it looked like there might be a big contest to see who would take over from Joe Biden, the party appears to be largely coalescing around Ms Harris.
People who had been seen as possible challengers to the vice president - Michigan Governor Gretchen Whitmer and Pennsylvania Governor Josh Shapiro, for instance - have instead endorsed her.
While it's possible that another name emerges - whether to mount a serious challenge or to provoke debate - it does look like the wind is behind Ms Harris's nascent campaign at the moment.
What happens at the Democratic National Convention?
Starting 19 August, the Democratic National Convention is a huge gathering of the party's delegates, senior figures and supporters.
There, the party's 4,000 or so delegates (and a few hundred superdelegates) usually vote for who the presidential nominee should be. The vast majority had been pledged to Mr Biden, but they are now free to vote for anyone.
Voting takes place in rounds, with any prospective nominees eliminated until one person is left with more than 50% of the votes.
That said, it's possible that Democrats won't wait until the convention and instead work out some way of ensuring the potential nominee is decided before the convention, so delegates rally around the chosen pick.
CNN and other US media are reporting the Democratic National Committee is moving forward with a process that could determine the nominee by 7 August.
This deadline, the Democratic National Committee says, is critical to ensure that the new president-VP candidate pair can get on to the ballot in all states and avoid the risk of litigation.
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What about the VP pick?
This generally is a more informal process.
The chosen presidential nominee will be given time to choose their candidate, who is then usually accepted on to the ticket.
CNN cited Democrat officials saying the future nominee would have until 7 August to finalise their choice, but the exact schedule would be up to them.
Assuming the nominee is Ms Harris - this is not yet a done deal - there are a number of senior Democrat figures who have endorsed her that might make sense to be her VP.
They include high-profile state governors like Josh Shapiro and Gretchen Whitmer and other names like Senator Mark Kelly.
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Other key dates to know
The second Trump-Biden debate had been scheduled for 10 September, but it remains to be seen if that will go ahead as planned.
There had already been some doubt that Mr Biden would take part in that event, and Ms Harris's team may have other changes they wish to make to the date, network and format.
Election day is 5 November, but many states have early voting - some beginning as soon as late September.