WILMINGTON/WASHINGTON — US President Donald Trump was narrowly leading Democratic rival Joe Biden in the vital battleground state of Florida on Tuesday (Nov 3), while other competitive swing states that will help decide the election outcome, such as Georgia and North Carolina, remained up in the air.

The two contenders split the first US states to be projected in the White House race, with conservative Indiana and Kentucky going to Mr Trump and Democratic-leaning Vermont and Virginia going to Mr Biden, according to projections by television networks and Edison Research.

But in Florida, a must-win state for Mr Trump in his quest for the 270 electoral votes needed to win the presidency, Mr Trump was leading Biden 50.3 per cent to 48.7 per cent with about 89 per cent reported.

Mr Biden still has multiple paths to the 270 electoral votes he needs without Florida despite having spent lots of time and money trying to flip the state that backed Mr Trump in 2016.

The winner — who may not be determined for days — will lead a nation strained by a pandemic that has killed more than 231,000 people and left millions more jobless, racial tensions and political polarisation that has only worsened during a vitriolic campaign.

A third of US voters listed the economy as the issue that mattered most to them when deciding their choice for president while two out of 10 cited Covid-19, according to an Edison Research exit poll on Tuesday.

In the national exit poll, four out of 10 voters said they thought the effort to contain the virus was going "very badly."

In the battleground states of Florida and North Carolina, battleground states that could decide the election, five of 10 voters said the national response to the pandemic was going "somewhat or very badly."

The poll found that nine out of 10 voters had already decided whom to vote for before October, and nine out of 10 voters said they were confident their state would accurately count votes.

The poll found some signs of slippage in support for Mr Trump. In Georgia, Mr Trump was winning with five of 10 white men with college degrees, down from eight in 10 in 2016, and five in 10 college graduates, down from seven in 10 in 2016.

Mr Biden, the Democratic former US Vice President, has put Mr Trump's handling of the pandemic at the centre of his campaign and has held a consistent lead in national opinion polls over the Republican president.

Mr Biden, 77, appeared to have multiple paths to victory in the state-by-state Electoral College that determines the winner; at least 270 electoral votes, determined in part by a state's population, are needed to win.

Opinion polls show Mr Trump, 74, is close enough in several election battleground states that he could repeat the type of upset he pulled off in 2016, when he defeated Democrat Hillary Clinton despite losing the national popular vote by about three million ballots.

The vote results will start to trickle in after 7pm EST (8am Wednesday, Singapore time) but counting could go on for several days in many states.

"I'm hopeful," Mr Biden told reporters in his home state of Delaware, after earlier appearing in the pivotal state of Pennsylvania to make an 11th-hour appeal to voters.

"What I'm hearing," Mr Biden added, "is that there's overwhelming turnout, and overwhelming turnout particularly of young people, of women" and in some states of older Black voters — groups expected to favour him.

"I think we're going to have a great night," Mr Trump said in Arlington, Virginia, across the Potomac River from Washington, where he thanked campaign workers. "But it's politics and it's elections, and you never know."

"Winning is easy. Losing is never easy — not for me it's not," Mr Trump added.

Ahead of Election Day, just over 100 million voters cast early ballots either by mail or in person, according to the US Elections Project at the University of Florida, driven by concerns about crowded polling places during the pandemic as well as extraordinary enthusiasm.

The total has broken records and prompted some experts to predict the highest voting rates since 1908 and that the vote total could reach 160 million, topping the 138 million cast in 2016.

Mr Trump, admitting his voice was "a bit choppy" after making speeches at numerous raucous rallies in the final days of the campaign, said he was not yet thinking about making a concession speech or acceptance speech.

Seeking a second four-year term, Mr Trump said he would not declare victory prematurely, adding "there's no reason to play games."

In Pennsylvania, Mr Biden first stopped at his childhood home in Scranton, where he signed one of the living room walls, writing: "From this house to the White House with the grace of God. Joe Biden 11-3-2020."

He later visited Philadelphia and used a bullhorn to address supporters who chanted, "Joe, Joe, Joe."

"It ain't over till it's over," Mr Biden said in front of a block of brick rowhouses.

In anticipation of possible protests, some buildings and stores were boarded up in cities including Washington, Los Angeles and New York. Federal authorities erected a new fence around the White House perimeter.

A REFERENDUM ON TRUMP

Supporters of both candidates called the election a referendum on Mr Trump and his tumultuous first term. No US president has lost a re-election bid since Republican George H W Bush in 1992.

In Atlanta, Mr Cody Sellers, 32, a registered Republican and project manager at a home improvement store, voted for Mr Biden.

"Trump is the issue," Mr Sellers said, shivering in the cold.

"I really think Trump is bad for our country," he added. "He's divisive. We're on a path to trouble. I'm not thrilled about Biden, but he can do the job and he cares about our country."

Polling shows Georgia, long a Republican stronghold, might be up for grabs this year but Mr Victor Akinola, 44, stuck with Mr Trump.

"The hopes that liberals have for a so-called blue wave is unfounded. Georgians won't vote en masse against their own local interests," said Mr Akinola, who works in information technology.

Among the most closely contested states that are expected to determine the outcome are Pennsylvania, Florida, Wisconsin, Michigan, North Carolina, Arizona and Georgia, with Democrats hoping that Mr Biden may even threaten Mr Trump in states that once seemed certain to go Republican such as Ohio, Iowa and Texas.

Voters on Tuesday will also decide which political party controls the US Congress for the next two years, with Democrats narrowly favoured to recapture a Senate majority and retain their control of the House of Representatives.

Mr Trump is seeking another term in office after a chaotic four years marked by the coronavirus crisis, an economy battered by pandemic shutdowns, an impeachment drama, inquiries into Russian election interference, US racial tensions and contentious immigration policies.

Mr Biden is looking to win the presidency on his third attempt after a five-decade political career including eight years as vice president under Mr Trump's predecessor, Mr Barack Obama.

Mr Biden has promised a renewed effort to fight the public health crisis, fix the economy and bridge America's political divide. The country this year was also shaken by months of protests against racism and police brutality.