The 2024 could prove to be among the most consequential in American history.
And it could not be closer, or more difficult to predict the outcome.
If wins, he'll be older, angrier and than he was in his first term.
There'll be nobody around to cool his temper.
And former members of his senior staff have issued stark warnings that the former President speaks and , and would likely continue to do so in office.
If he loses, he will most likely try and overturn the result, just as he did on January 6 2021.
He has employed an army of angry activists whose primary function is to "stop the steal" - finding any reason to question, undermine or overrule votes and results that don't go Trump's way.
After an initial poll boost after taking over from as nominee, Kamala Harris' numbers have settled down. It's a genuine 50/50 toss-up, and will most likely either be decided by turnout or in the courts.
But when will we find out the result of the US election? Here's what we know so far.
Will we know the US election result on election night?Almost certainly not. The US election isn't run like the UK - there's no enormous nationwide exit poll, and the sheer size of the electorate means counting and verifying votes will take some time - even with electronic machines and early voting.
When will we know the result of the US election?We'll get results state by state - and places where there has been a clear winner will be declared quite quickly.
However the key swing states where the polls are closer will take much longer. In particular, the knife-edge state Pennsylvania is likely to take days - if not weeks - to certify its result.
When we know who the next US President is will come down to how close it was.
In 2020 it came down to a few swing states, but the end result wasn't that close - and it still took several days to call the winner.
What happens after the election result is confirmed?The winner becomes President Elect, but doesn't take office until January.
The winning candidate will give a speech outside the US Capital building on January 20th, when they will take the oath of office and become President.
But it was those 76 days that proved particularly dangerous in 2020-21 - with Trump refusing to concede, and eventually holding his "stop the steal" rally outside the White House on January 6th.
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