Washington, Nov 9 

US presidential candidates Hillary Clinton and Donald Trump cast their ballots on Tuesday morning.

The Republican presidential candidate, Donald Trump, his wife Melania and daughter Ivanka, cast their ballots in Manhattan, the Washington Post reported.

Trump gave high-fives to two children inside the East 56th Street polling centre near Trump Tower.

When asked what he'll do if the networks call the election for Democrat Hillary Clinton, Trump said, "We'll see what happens."

"It's really good. Right now; it's looking really good," he told reporters after he voted.

Democrat Hillary Clinton and her husband and former US President, Bill Clinton, voted in Chappaqua, New York.

"I know how much responsibility goes with this and so many people are counting on the outcome of this election, what it means for our country, and I'll do the very best I can if I am fortunate enough to win today," she told CNN.

Mike Pence casts his ballot in Indianapolis

US Republican Vice-Presidential candidate Mike Pence and his wife, Nancy, cast their ballots in US presidential election on Tuesday.

The couple walked from the Governor's mansion, a few miles outside of Indianapolis, to a polling centre a block away, according to CNN Politics. They arrived shortly before noon at the St. Thomas Aquinas School, The Washington Post reported.

The two took a morning bike ride earlier "to kick off Election Day", Pence wrote in a tweet.

Pence's running mate, Donald Trump, cast his ballot at about 11 a.m. at a polling centre in Manhattan.

On Sunday, Pence told host Chris Wallace on Fox News that the Trump campaign will "accept a clear election outcome".

"Donald Trump is going to win this election. He will be more than happy to accept the results," Pence said. 

"Chris, the campaign -- yes, the campaign has made it very clear, that, you know, a clear -- a clear outcome obviously both sides will accept. But I think both campaigns have also been very clear that, you know, in the event of disputed results, they reserve all legal rights and remedies," he added.