Swing states make or break every US election, and the final leg of the race between Donald Trump and Joe Biden is underway – with all to play for given narrowing polls and odds. The American voting system is very different to the UK’s – even though Americans go out and cast their vote for either Mr Biden or Mr Trump this year, they are actually voting on a state level, not a national level.
Votes are cast for the Electoral College in all 50 states – and the amount of college seats in each state is proportionate to its population.
Florida has 29 Electoral College votes to give out – so there’s a lot at stake when casting a vote in the sunshine state.
The Electoral College system does usually reflect the popular vote – presidents have won the electoral vote while losing the popular vote just five times in US history.
The most recent instance was in 2016, when Mr Trump won the electoral college but Hillary Clinton, his Democratic opponent, won the popular vote.
Swing states have populations that are finely politically divided between Democrat and Republican.
Most states nearly always vote the same way, meaning that in reality there are just a handful of states where both candidates stand a chance of winning.
Between elections, they swing from one party to another – unlike solid states such as California, which has always voted blue.
There are some permanent swing states, such as Florida – but others change in the run-up to an election.
It is highly unlikely the president will win the election if he loses Florida, given that Mr Biden is also polling ahead, albeit slightly, in other swing states.
The good news for Trump is that history does indicate how difficult it would be for Biden to win the state by a large margin.
The last time a Democrat won the state by more than six points was 1948.
No candidate from either party has won the state by more than 6 points since 1992.