Early indications are that the polls have been proved wrong in many cases, with several swing states showing strong support for Donald Trump.
Despite that, Joe Biden looks as though he has gained Arizona, a state that has been Republican for many years.
The election is still too close to call, but there are some trends in voting patterns that have become apparent.
1. Coronavirus may be key
Donald Trump’s attitude to the pandemic has split America, with many of those concerned by the level of infection in the country shocked at his approach to controlling its spread.
But many in the US say he speaks for them, due to their reluctance to wear masks or to have their livelihoods affected by lockdowns.
The arguments have raged as the US has seen more cases than any other nation across the globe and more than 230,000 deaths.
Experts have said these factors may have had an impact on the way people have voted in several of the battleground states.
Former Republican presidential adviser Lanhee Chen told Sky News that some in several Democrat led-states – which have seen tougher restrictions – particularly in the industrial north, could have voted for President Trump because they supported his approach.
He said: “The coronavirus lockdowns, those are a very divisive issue. For Trump, he clearly rode this issue in Michigan, and used it to his advantage.”
Political scientist Ashley Koenig said: “We do know that COVID has become very much polarised. It was a bi-partisan or non-partisan issue when it first went through the United States and now it’s become highly polarised so now there becomes this pitting against of the economy versus health and we’ve already seen some of the numbers in the exit polls… and there could be this contentious debates between those who feel the economy needs to move on, because they are losing their livelihood, their paychecks, versus those who want to uphold the safety of society.”
2. The Latino vote varied from state to state
Florida
In Florida, 48% of Latinos backed Donald Trump, possibly tipping the balance in the incumbent’s favour. Democrats on the ground say they believe it was the Latino vote that was key to the President’s success in the state, which would have been critical if Joe Biden was to win.
Mr Trump was declared the winner in Florida after 96% of the votes were counted.
Bradley Jackson, a Democrat activist in Florida, told Sky News: “One of the main things I did see was down in Miami Dade county – which is a Democratic stronghold – that the Hispanic population, mainly Cuban and Venezuelan, which have had socialist governments for so long, have taken that message that the GOP have put out, calling Joe Biden a socialist and used that to convince people that this agenda is what is happening. A lot of them may have come out and voted and may have done worse than Hillary Clinton’s lead, for Joe Biden this year.”
Arizona
In Arizona, the opposite appeared to be the case, with many putting signs of Democrat success down to the changing demographics in the state, which mirror others nearby where the number of Latino voters has increased in recent years.
The state is yet to be called but Mr Biden had an early lead.
Mr Chen said: “That reflects the changing nature of the Republican coalition. Arizona has only voted for a Democrat one other time in the last 70 years so it does represent a realignment. That entire region has previously been much more competitive and now appears to be tipping over to the Democrats and it shows you the strategy Trump has pursued – to drive up his support with that non-college educated White vote.”
3. The industrial north will decide it
Ohio is the ultimate bellwether state which Trump secured in 2016 with his appeal to its sizeable group of non-college educated white voters. His focus on manufacturing and the problems caused by outsourcing made the difference in eastern Ohio which had long voted Democrat but swung sharply right.
In 2020, Mr Trump increased his vote by at least 150,000 on the 2016 result.
The Blue Wall consists of states that for numerous recent elections have gone Democrat but in 2016, the Rust Belt states within it turned largely red.
If what has happened in Ohio – which is also a northern state with large industrial areas – happens across the Blue Wall states of the north (Pennsylvania, Michigan, Wisconsin), then it could spell defeat for Joe Biden.
Sky correspondent Cordelia Lynch says there are signs that Donald Trump has improved his turnout in those states on 2016.
She says this is because states like Ohio are trending whiter, righter and older.
4. “Shy Trumpers” came out
Many commentators have said that the polls may have been wrong because of a phenomenon call the Shy Trumper – voters who did not tell pollsters they planned to vote Trump, and then did.
Mr Chen told Sky News: “Biden was winning by a much larger margin. Polls are a reflection of assumptions about who will turn out to vote and pollsters have to do their best to guess who is going to turn out on election day.
“Clearly what Trump has been able to do in these states is to create electorate that are more favourable to him. He’s turning out voters that are going to support him and demotivating those who would oppose him.”