Voters across 50 states are preparing to cast their ballots after a bitterly contested US election campaign, which will see Donald Trump or Kamala Harris become president.
In the last few hours, both candidates have been giving their final pitches. “The momentum is on our side,” Ms Harris told a crowd in Philadelphia that chanted back, “We will win”.
“Tonight, then, we finish as we started: with optimism, with energy, with joy,” she said, while enjoying the support of celebrity endorsements on the day from Katy Perry, Lady Gaga and Jon Bon Jovi.
In contrast, Mr Trump ended his campaign in Michigan, repeating key messages about the economy and immigration.
A handful of states will play a crucial role in determining the outcome of the election. Arizona, Georgia, Michigan, Nevada, North Carolina, Pennsylvania and Wisconsin hold the keys to the White House.
To become president, the winning candidate needs 270 electoral votes or more, with each state carrying a different number of votes.
But the focus has been on Pennsylvania which carries 19 electoral votes, the most of all the swing states.
It has been a remarkable journey for both candidates – with Mr Trump surviving two assassination attempts and Ms Harris not even originally in the running.
Katy Perry performed in Pittsburgh in support of Kamala Harris. Pic: AP
For more than a year, the 2024 presidential race seemed destined for a rematch between Joe Biden and Mr Trump – but a disastrous TV debate by Mr Biden eventually forced him to withdraw from the ticket.
The Democratic party’s decision to replace Mr Biden with his vice president transformed the race and shifted polls in Ms Harris’s favour. But only just.
Many polls are too tight to call and, with a large margin of error, most experts are refusing to predict the outcome.
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Later, attention will turn to those battleground states including Georgia, which is among the first polls to close at 7pm local time (midnight UK time).
State election officials told Sky News they could have a result as early as 10pm (3am UK time).
Even so, it could be several days before the US has a definitive result.
Voters are not just selecting a president. In addition, 10 states will hold abortion-related ballots, half of which would overturn existing restrictions.
Predict who you think will win in each swing state and we’ll tell you who the president will be if you’re right.
Tonight, Sky News will have access to the most comprehensive exit poll and vote-counting results from every state, county and demographic across America through its US-partner network NBC.
You can find out more about Sky News’ coverage here.