Donald Trump is projected to win the key state of Ohio, with 53.3 percent of the vote, CNN reports.
A "Make America Great Again" hat sits in a glass case during Republican presidential nominee Donald Trump's election night party at the New York Hilton Midtown on November 8, 2016 in New York City. Chip Somodevilla/Getty Images/AFP
Supporters of Republican presidential nominee Donald Trump watch results unfold on a TV screen during election night at the New York Hilton Midtown in New York on November 8, 2016. AFP / Mandel NGAN
Media stand on risers below an American flag ahead of Democratic presidential nominee former Secretary of State Hillary Clinton's event on election night at the Jacob K. Javits Convention Center November 8, 2016 in New York City. Elsa/Getty Images/AFP
People cheer as they watch voting results at Democratic presidential nominee former Secretary of State Hillary Clinton's election night event at the Jacob K. Javits Convention Center November 8, 2016 in New York City. Elsa/Getty Images/AFP
People take a look on the Empires State Building as it is seen lit in Blue, Red and White colors before the closing polls during the presidential election on November 8, 2016. in Weehawken, New Jersey. AFP
People watch elections returns during election night at the Jacob K. Javits Convention Center in New York on November 8, 2016. AFP PHOTO / DON EMMERT
A cake in the likeness of Republican presidential nominee Donald Trump is on display at his election night event at the New York Hilton Midtown in New York on November 8, 2016. AFP PHOTO / Timothy A. CLARY
People wait in line to vote at a poll station in Arlington, Virginia on November 8, 2016. AFP / Andrew CABALLERO-REYNOLDS
A roll of I Voted stickers sits on a table at Oakman Elementary School during the US presidential election on November 8, 2016 in Dearborn, Michigan. AFP / JEFF KOWALSKY
Voters cast ballots at a polling station at the Big Bear Lake Methodist Church in Big Bear, California, November 8, 2016. AFP / Bill Wechter
Voters wait in line in front of a polling station to cast their ballots in the US presidential election in Scottsdale, Arizona on November 8, 2016. AFP / Laura SEGALL
People vote on election day at Brooklyn Avenue Elementary School in the primarily Latino East LA neighborhood of Boyle Heights on November 8, 2016 in Los Angeles, California. / AFP / Frederic J. BROWN
People wait in line cast their vote at Samuels Community Center as New York voters turn out to vote in the presidential election November 8, 2016 in Harlem, New York City. AFP
People vote on the US presidential election at Santa Monica City Hall on November 8, 2016 in Santa Monica, California. AFP / Frederic J. BROWN
Republican presidential nominee Donald Trump gives the thumbs-up after he and his wife Melania (R) submitted their ballots at a polling station in a school during the 2016 presidential elections on November 8, 2016 in New York. / AFP PHOTO / MANDEL NGAN
Supporters of Republican presidential nominee Donald Trump gather outside Trump Tower in New York City on election day November 8, 2016. AFP PHOTO / DOMINICK REUTER
Democratic presidential nominee Hillary Clinton (c) shakes hands with supporters after casting her vote in Chappaqua, New York on November 08, 2016. AFP
People stand in line outside a polling station located at Trump Place, November 8, 2016 in New York. AFP / Bryan R. Smith
People cast their votes for US president November 8, 2016, at Centerville High School, in Centreville, Virginia. AFP / PAUL J. RICHARDS
Other battleground states, including Florida, Virginia, North Carolina and Georgia, were still too close to call.
This would give Democrat candidate Hillary Clinton 109 of the 270 electoral votes needed to win, and Mr Trump would have 167, CNN reported.
In other recent states to be called, Mrs Clinton won New York and Connecticut. Mr Trump won Texas and Arkansas.
Early predicted victories
Earlier, Mrs Clinton got a series of expected wins, including in Vermont, Massachusetts, Maryland, Rhode Island, New Jersey, Illinois, Delaware and the District of Columbia.
South Carolina, Alabama, Indiana, West Virginia, Kentucky, Oklahoma, Tennessee and Mississippi, among others, went to her Republican rival.
The early victories for both in these states were long-predicted.
'I want to see everything honest' - Trump
Earlier, Mr Trump said he would have to "see how things play out" before accepting the final election results. He said he had seen reports of voting irregularities, including that machines were changing votes, but gave few details.
Mr Trump was tipped to win the key state of Ohio, CNN reported.
Photo: AFP
American voters reported long lines and isolated cases of harassment at polling places, but fears of bigger problems did not appear to have materialised.
Local media reported that touch-screen voting machines were not recording ballots correctly in several Pennsylvania counties.
Civil rights groups said voters had complained of intimidating behaviour at polling booths in Pennsylvania and Florida as supporters of both candidates cast their ballots.
A Democratic Party source said the Clinton campaign had not encountered systemic problems beyond the usual election day hiccups.
Mrs Clinton cast her ballot at an elementary school near her home in Chappaqua, New York early on Tuesday morning.
"It is the most humbling feeling. I know how much responsibility goes with this," Mrs Clinton said.
Mr Trump, who voted in Manhattan, said it was a tremendous honour to cast his ballot.
No presidential vote from Bush
Former Republican president George W Bush and his wife, Laura, did not cast a vote for US president on Tuesday but did vote for Republicans in down-ballot races, a spokesman for Mr Bush said.
"They voted 'None of the Above' for president," Freddy Ford said in an email about the couple, who now live in Dallas.
In a break from custom, neither Mr Bush, president from 2001 to 2009, nor his father, former Republican president George H W Bush, endorsed the Republican nominee for president, New York businessman Donald Trump.
Jeb Bush, the younger brother of George W Bush and the son of George H W Bush, ran against Mr Trump in the acrimonious and insult-laced Republican nominating contest this year.
- Reuters / BBC
