First Thing: Americans head to polls with historic election on a knife edge

Trump launched insults at his final rally as Harris ended her campaign calling for people to get out the vote'. Plus, Nate Silver's final election forecast

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Good morning.

Tens of millions of voters will cast their ballots on Tuesday in one of the tightest and most divided presidential elections in modern US history, with Kamala Harris and Donald Trump locked in a dead heat.

Why is Pennsylvania so crucial? It has the most electoral votes - 19 - of the battleground states.

Who is Silver? The forecaster called 49 out of 50 states in the 2008 election, as well as the outcome of the 2012 and 2020 races. Take it with a pinch of salt though - in 2016, he gave Trump only a 28.6% chance of becoming president.