Donald Trump has gained a lead over Kamala Harris in several of the swing states that will decide who becomes the next US president, nail-biting early projections suggest.
The BBC’s US partner CBS says Georgia and North Carolina are leaning towards Trump and he is narrowly ahead in Wisconsin and Pennsylvania, while Harris has the advantage in Michigan. But leads are fluctuating by the minute.
Trump has won conservative strongholds including Florida and Idaho, while Kamala Harris is sweeping liberal bastions from New York to California, CBS projects.
Whichever way it goes the result will be historic – giving America its first woman president or marking a seismic political comeback for Trump.
A high turnout has been predicted, but the final outcome may not be known for several days if the results are as close as polls have indicated.
A potential red flag for Harris has emerged in the latest CBS exit poll data, which suggests that 54% of women have voted for her. Joe Biden won the support of 57% of women in 2020.
Whoever wins the White House may have their hands tied by Congress, which is also up for grabs in Tuesday’s vote.
Democrats have a slim majority in the Senate, while Trump’s fellow Republicans narrowly control the House of Representatives.
Republicans took a step towards winning control of the Senate on Tuesday night by wresting a seat in West Virginia from the Democrats and beating off a stiff challenge in Texas.
But neither party seemed to have an advantage in the House.
The seven swing states expected to determine the outcome are Georgia, Arizona, Nevada, North Carolina, Michigan, Wisconsin and Pennsylvania.
Early results suggest the race remains very tight in Arizona and Wisconsin, while no returns have emerged yet from the battleground of Nevada.
Around 86 million voters cast their ballots early amid one of the most turbulent campaigns in recent American history.
Vice-President Harris, 60, only became the Democratic Party candidate in July, after President Joe Biden withdrew from the race under pressure from within the party.
Trump, 78, was the target of two assassination plots – narrowly avoiding a sniper’s bullet in Pennsylvania.
The former president said he felt “very confident” as he voted earlier in the day near his home in Palm Beach, Florida, with his wife, Melania.
“If I lose an election, if it’s a fair election, I’m going to be the first one to acknowledge it,” he said.
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He posted earlier on his social media platform, Truth Social, saying “law enforcement coming” to Philadelphia because of “massive cheating”.
Philadelphia’s police department told BBC Verify they were unaware of any electoral fraud. The city’s top prosecutor said the allegation had “no factual basis whatsoever”.
Both sides have armies of lawyers on standby for legal challenges on and after election day.
Elon Musk, the world’s richest man and Trump mega-donor, is spending election night with the Republican nominee at his Mar-a Lago resort in Florida.
Harris, who voted early by mail in her home state of California, is due later to address students at Howard University, a historically black college in Washington DC, where she was an undergraduate.
“To go back tonight to Howard University, my beloved alma mater, and be able to hopefully recognise this day for what it is is really full circle for me,” Harris said on a radio interview earlier.
If she wins, she would become the first woman, black woman and South-Asian American to win the presidency.
Trump would become the first president to win non-consecutive terms in more than 130 years. He is also the only president to be impeached twice and the first former president to be criminally convicted.
Exit polling by CBS also suggests that around a third of voters said the state of democracy was their top concern, out of the five options given.
The economy ranked second, with three in 10 voters choosing it, according to the preliminary data.
Abortion and immigration followed on the list, while foreign policy was deemed the least important.
Law enforcement agencies nationwide are on high alert for potential violence.
About 30 bomb threats hoaxes targeted election-related locations nationwide on Tuesday, more than half of them in the state of Georgia alone, reports CBS.
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