Millions of Americans voted Tuesday for their new leader in a historic election that will either elevate Democrat Hillary Clinton as their first woman president or hand power to maverick populist Donald Trump.

As the world held its collective breath, Americans were called to choose between two radically different visions for the most powerful nation on Earth.

While Clinton has a slim lead in polls, no one was ruling out a victory by her Republican rival Trump -- with the winner's name not expected to be known before 0300 GMT Wednesday.

In Virginia horse country, balmy south Florida, blue-collar Pennsylvania and crowded Manhattan long lines snaked into the streets outside polling stations.

"Hillary, she has a history," said Charmaine Smith, 50, an African-American retail manager as she cast her ballot in Harlem. "All Trump has is the bullying."

But R. Raju, a 70-year Indian immigrant from Staten Island, New York, cast a confident vote for the Republican and his promise to reclaim power from a corrupt Washington elite.

"Trump would be a great president," he said. "Not good, great. He's like a Ronald Reagan."

An hour's drive north, a crowd of admirers chanted "Madam President" as Clinton and husband Bill, the former president, voted near their home in Chappaqua, before emerging to shake hands and chat with the crowd.

"So many people are counting on the outcome of this election, what it means for our country," the 69-year-old secretary of state said. "And I'll do the very best I can if I'm fortunate enough to win today."


Don't let up

Trump also cast his ballot, alongside wife Melania in a Manhattan school gymnasium.

"Right now it's looking very good," he told reporters -- paying no heed to protesters who welcomed him with chants of "New York hates you!"

But as the clocked ticked down towards the close of East Coast polling stations, the Republican issued a last-minute appeal to voters in key battleground Florida -- without which his path to the presidency is slim at best.

"Don't let up, keep getting out to vote - this election is FAR FROM OVER! We are doing well but there is much time left. GO FLORIDA!" Trump tweeted -- looking to garner 11th hour votes.

The 2016 race is the most bruising in modern memory. Barack Obama's election eight years ago as the nation's first black president had raised hopes of uniting Americans under a common banner, but the current contest has only highlighted the country's divisions.

Trump's campaign spooked world markets seeking stability after the recent global slowdown, but stocks rose for a second straight day Tuesday on the expectation that Clinton will prevail.

At the closing bell, the S&P 500 closed up 0.4 percent.

A polling average by tracker site RealClearPolitics gave Clinton a 3.3-percentage point national lead, but Trump is closer or even has the advantage in several of the swing states that he must conquer to pull off an upset.


'La Senora'

Early voting has shown particular enthusiasm among Hispanic voters, an increasingly influential voting bloc whose strong turnout could shape Tuesday's results.

In the heavily Latino neighborhood of East Los Angeles, Mexican-Americans Margarito Salinas, 88, and friend Guadalupe Cobian, 64 said their choice was an easy one.

"That guy is a Nazi," Salinas said of Trump. "My vote is for La Senora."

Clinton conducted six radio interviews Tuesday in the lull after voting when candidates suddenly have hours of downtime following a non-stop campaign, urged citizens in battleground states to unite and vote for a more "big-hearted" America.

"I hope to be remembered as someone who began to help heal our country, to overcome the divide, the very unfortunate feeling that a lot of people have that this election was very much filled with nastiness and negativity," she told WOKQ radio.

Trump pressed his message with voters who feel left behind by globalization and social change, wrapping up with a flourish in Michigan after midnight and predicting a historic upset.

"Today the American working class is going to strike back, finally," he said.


Nevada legal challenge

The first poll closures come at 6:00 pm (2300 GMT) on the US East Coast, but it may be hours before the results become clear.

Even then, questions remain. Trump has repeatedly claimed Democrats and the media are seeking to rig the race and said last month that he may not accept the result if he thinks voting is unfair.

Asked at his voting location whether he would concede if networks call the election for Clinton, Trump said: "We'll see what happens."

In a sign that Trump is preparing an aggressive poll-related legal challenge, his attorneys filed a lawsuit Tuesday in Nevada alleging that the Clark County registrar of voters kept early voting stations open hours beyond the designated closing time.

Meanwhile the campaigns' armies of volunteers were making last-ditch phone calls to get residents in battleground states to the polls.

Clinton has pushed an optimistic vision, despite a wobble in recent weeks when the FBI reopened an investigation into whether she had put US secrets at risk by using a private email server -- only to close the probe again on Sunday.

In a radio interview on the last night of the campaign, she said the matter was behind her, and she courted voters at her final rallies in Philadelphia with President Barack Obama and rocker Bruce Springsteen, and in North Carolina with pop diva Lady Gaga.

The first poll closures come at 6:00 pm (2300 GMT) on the US East Coast, but it may be hours before the results become clear.

Even then, questions remain. Trump has repeatedly claimed Democrats and the media are seeking to rig the race and said last month that he may not accept the result if he thinks voting is unfair.

Asked at his voting location whether he would concede if networks call the election for Clinton, Trump said: "We'll see what happens."

In a sign that Trump is preparing an aggressive poll-related legal challenge, his attorneys filed a lawsuit Tuesday in Nevada alleging that the Clark County registrar of voters kept early voting stations open hours beyond the designated closing time.

Meanwhile the campaigns' armies of volunteers were making last-ditch phone calls to get residents in battleground states to the polls.

Clinton has pushed an optimistic vision, despite a wobble in recent weeks when the FBI reopened an investigation into whether she had put US secrets at risk by using a private email server -- only to close the probe again on Sunday.

In a radio interview on the last night of the campaign, she said the matter was behind her, and she courted voters at her final rallies in Philadelphia with President Barack Obama and rocker Bruce Springsteen, and in North Carolina with pop diva Lady Gaga.