Americans are choosing whether Donald Trump or Joe Biden will be the next US president.
Here’s what to watch for as an unpredictable election night unfolds, and the results roll in.
Some key details:
- To become US president, you don’t actually need to win the popular vote. Instead, candidates are aiming to win the majority in something called the electoral college (more on that below)
- Millions more Americans are voting by mail than in previous elections. Counting postal votes can take more time, and some states won’t start until polling day, so there will almost certainly be delays for some results.
- And because of this unprecedented surge of postal votes, a candidate who takes an early lead may end up being overtaken as postal or in-person votes are tallied. So be wary of the numbers.
Some key terms:
- Bellwether state: Places like Ohio and Missouri where voters have proven reliable at choosing the national winner
- Exit poll: Interviews with voters after they have voted. These include people who vote on the day and early voters. Only a small number of voters are interviewed, so the exit poll result can turn out to be different to the official count.
- Electoral college: Each state gets a number of electors, roughly in proportion to its population. In most cases, whichever candidate wins a state also wins all that state’s electors, who meet later to choose the president and vice-president. Because there are 538 electoral college votes, each candidate needs 270 to win. There’s a full explanation of the system here.
- Projecting winners: This is what the night is all about but how does it work? It’s a combination of in-person interviews with voters at polling stations, telephone interviews with early voters and actual votes counted in precincts. Major US networks will project (they may use the term “call”) winners of states when all this data shows a candidate has an unbeatable lead. In all cases, these are predictions and not official results, which usually take weeks. (More on projecting below)
- Swing state or battleground state: These states lack a clear party affiliation, meaning they are up for grabs for both Democratic and Republican candidates.
- Red state v blue state: These states tend to vote with a particular party – Republicans in red states and Democrats in blue.
How to know who’s winning
The influx of postal ballots this year will make it hard to see who’s in the lead early on.
Different states have different rules for how – and when – to count postal ballots, meaning there will be large gaps between them in terms of reporting results. Some states, like Florida and Arizona, begin pre-processing ballots weeks before 3 November. Others, like Wisconsin and Pennsylvania, won’t touch these votes until election day, meaning they’ll likely be slower to count.
To add to the confusion, states differ in their deadlines for when to accept postal ballots. Some, like Georgia, will only count ballots received on or before 3 November, while others, like Ohio, will count late ballots as long as they are postmarked by 3 November.
If some of the contests in the battleground states are close, then we might not know those results – and therefore the overall winner – until much later, possibly for several days.