Staying Up? Key Results To Watch Out For - And When They Could Emerge

A reminder of the basics: whether Donald Trump or Kamala Harris is the next president will be decided by the electoral college rather than a straight count of the national vote - meaning that the winner will be the person who gets to a simple majority of 270 of the 538 electors on offer across the 50 states, whether or not they get more votes than their opponent nationwide.

- Archie Bland

That means that the result is quite likely to come down to who prevails in the seven battleground states identified by both sides as being up for grabs: Arizona, Georgia, Michigan, Nevada, North Carolina, Pennsylvania and Wisconsin.

Meanwhile, all 435 seats in the House of Representatives are on the ballot, as are 34 of the 100 seats in the Senate. There are also 13 state and territorial governorships to be decided.

The election will be covered by the BBC, ITV, Channel 4, Sky News and various others. The Guardian live blog will also be running, obviously.

Here is a guide to how the night will unfold. UK viewers should consider getting some sleep at 8pm or 9pm, and setting alarms for midnight or 1am, since not much will happen before that.

10pm

Exit polls give context

Polls are still open, but the first batch of exit polls are released.

Unlike in the UK, where exit polls are a pretty robust guide to the final outcome, the American version offers only a tantalising hint of what may be in store: rather than providing a projection of final results on the basis of asking people at polling stations how they voted, they give a view of what respondents said were the issues that mattered the most to them.

They're based on a bigger sample than typical polls - numbering in the tens of thousands - so they ought to give pretty robust findings. But knowing that voters were motivated by the economy or abortion, for example, will only be a clue to how the night might go, rather than a basis for projecting the result.

Midnight

Georgia and North Carolina

Polls close in six states over the next hour. Don't just follow the running count of electoral college votes to get a sense of how it's going, though: Trump is expected to have the biggest tally coming out of this first batch however well his night's going.