Donald Trump and Hillary Clinton ended their marathon presidential campaigns with help from their superstar friends in the hours before the polling boothes opened Tuesday.

Ms Clinton’s final rallies were headlined by entertainers Jay Z, Beyonce, Lady Gaga, Bon Jovi and Bruce Springsteen, while Mr Trump enlisted the help of three of his adult children Ivanka, Eric and Donald Jnr, plus former Republican vice-presidential nominee Sarah Palin.

Democratic candidate Ms Clinton was also joined in Philadelphia by President Barack Obama, vice president Joe Biden and First Lady Michelle Obama, who the New York Times labelled “perhaps the most popular political figure in the country”.

Ms Clinton’s last-minute rush for votes took in Pennsylvania, Michigan and a midnight rally in North Carolina. Mr Trump opted to visit Florida, North Carolina, Pennsylvania, New Hampshire and Michigan.

All are battleground states, key areas to win if either Mr Trump or Ms Clinton want to realise their dream of becoming president by Tuesday evening in the US (Wednesday afternoon AEDT).

Cheekily, Mr Trump’s official schedule for election night read “Donald J. Trump Victory Party”, while Ms Clinton’s simply stated an “Election Event”.

And despite a lack of star power in the face of Ms Clinton’s high-profile allies, Mr Trump wasn’t short of his characteristic bravado.

“Beyonce and Jay Z,” Mr Trump said. “I like them [but] I get bigger crowds than they do.”

“Is there any place better to be than a Trump rally?” he then asked in North Carolina. “We’re having fun. And I don’t have a guitar and I don’t have a piano.”

Mr Trump was combative to the end, slamming Ms Clinton as the “face of failure” at his Pennsylvania event.

Having made the now-closed FBI review into Ms Clinton’s emails crucial to his campaign, he argued a “totally rigged system” was aiding her.

Donald Trump, Donald Trump Jr, Vanessa Trump, Jared Kushner, Ivanka Trump and Tiffany Trump arrive in New Hampshire. Photo: AAP

“You have one magnificent chance to beat the corrupt system and deliver justice,” Mr Trump said. “Do not let this opportunity slip away.”

Ms Clinton’s final message expressed dismay at how grubby the campaign had been.

She said she’d come to “regret deeply how angry the tone of the campaign became”.

She cast the choice facing voters on Tuesday as a “test of our time”.

Bruce Springsteen plays to thousands of Ms Clinton’s fans in Philadelphia. Photo: AAP

“We know enough about my opponent, we know who he is,” Clinton said, addressing tens of thousands at Philadelphia’s Independence Mall. “The real question for us is what kind of country we want to be.”

Mr Obama spoke urgently before Ms Clinton: “America, I’m betting on you one more time,” he said. “I am betting that tomorrow you will reject fear and choose hope.”

Mr Trump praised his supporters for having created a “movement”. But he warned it would all slip away if he lost on Tuesday.

“Go vote,” he urged. “Or honestly, we’ve all wasted our time.”

At least 45 million early votes have been cast early since mid October, according to Associated Press.

Experts predicted Mr Trump would have to win nearly all of the battleground states to become president, while Ms Clinton does not need a dream set of results for victory.

Watch Mr Obama fire up the rally:

“Are you fired up? Ready to go? Fired up? Ready to go?” Pres. Obama calls out to NH crowd https://t.co/UYpqI3esEb https://t.co/4ggIsgKYVJ

— CNN (@CNN) November 7, 2016

– with AAP