Hillary Clinton's campaign touted its ground game one day before the US presidential election while Donald Trump's portrayed him as the candidate of change championed by enthusiastic voters.

The return to the campaigns' core strengths and longtime arguments came as polling continued to favour Clinton slightly, and as the candidates squeezed in final visits to battleground states.

"We're just looking at maximising our turnout operation everywhere," Clinton told reporters in New York before boarding her plane for the day's campaigning.

She stopped short of predicting she could add a Democratic takeover of the US Senate to a White House victory tomorrow, saying, "We're working hard to help all of the candidates because it would make a real difference in what we could get done."


Trump campaign manager Kellyanne Conway on MSNBC cited supporters in Minnesota who walked kilometres to a Trump event there yesterday as an illustration of the voters who would help solidify the upper Midwest for the Republican nominee.

"We obviously have had Team Clinton on the run in terms of where they're going to schedule and deploy their super surrogates in the final days," Conway said, adding that Trump would win Michigan despite the Clinton deployments.

Clinton, 69, and President Barack Obama were each scheduled to visit Michigan on today, as were Trump and his running-mate, Mike Pence. Clinton held a 4.7 percentage point lead in the state's RealClearPolitics polling average with third-party candidates included. Obama won the state's 16 Electoral College votes by wide margins in both his elections.

Trump, 70, would appeal to voters there and in Rust Belt states such as Pennsylvania because of his populist message, particularly on trade, Conway said.

"He talks about the rigged corrupt system not working for the common man," she said.

Clinton campaign manager Robby Mook said the Democratic nominee's team was focusing on states that have no or little early voting, but polls showed a tightening race starting in late October, when Clinton led by more than 11 points.

Clinton was also scheduled to campaign in Pennsylvania - including a star-studded Philadelphia rally with the President, first lady Michelle Obama, former President Bill Clinton, daughter Chelsea Clinton, and singers Bruce Springsteen and Jon Bon Jovi - and to finish the night at a North Carolina rally with her family.

Donald Trump takes a break from speaking to compare his face to a mask during a rally at Sarasota, Florida. Photo / AP
Donald Trump takes a break from speaking to compare his face to a mask during a rally at Sarasota, Florida. Photo / AP

Trump is continuing a gruelling pace and was scheduled to appear in Florida, North Carolina, Pennsylvania, New Hampshire, and Michigan. His three oldest children were expected to fan out to Iowa, Michigan, Virginia, and Pennsylvania. Other Trump surrogates expected on the trail included 2008 vice-presidential nominee Sarah Palin, former rivals Ben Carson and Rick Santorum, and former representative Michele Bachmann.

Pence was also set to campaign in Minnesota and Pennsylvania. Clinton's running-mate, Tim Kaine, planned stops in North Carolina before joining with Vice-President Joe Biden for rallies in Kaine's home state of Virginia.

Several polls gave Clinton an edge nationally, including a Bloomberg survey that had Clinton ahead by three percentage points. She had four-point leads in the NBC News/Wall Street Journal poll, the ABC News/Washington Post tracking poll, and the CBS News poll.

Only the CBS and Bloomberg surveys contacted voters yesterday, meaning few polls are likely to reflect the full effect of the news that, after reviewing recently discovered e-mails, FBI Director James Comey was sticking to his conclusion that Clinton's private e-mail use as Secretary of State didn't warrant criminal prosecution.

Nate Silver's FiveThirtyEight forecast a 68.3 per cent chance Clinton would win. The New York Times model gave her a better chance, 84 per cent.

The Democrats' outlook for retaking control of the US Senate was dimmer, at 50 per cent, according to FiveThirtyEight. The Cook Political Report projected Democratic gains of five to 20 seats in the US House, short of those needed to dislodge Speaker Paul Ryan's Republican majority.

Clinton's improved outlook in the final hours of the race was reflected in rallies of global stocks, commodities, and the Mexican peso and in a waning demand for havens including gold and the yen.

Trump cast doubt on the FBI process that led to Comey affirming his decision not to recommend charges against Clinton.

"You can't review 650,000 new emails in eight days. You can't do it, folks," Trump said yesterday at rally in Michigan. "Now it's up to the American people to deliver justice at the ballot box."

Those figures refer to the number of emails thought to be discovered recently on the laptop of Anthony Weiner, the estranged husband of top Clinton aide Huma Abedin, during an investigation unrelated to the Clinton probe. Comey announced a review of those messages at the end of October.

Trump has linked the developments to a closing message about cleaning up corruption in Washington. "It is time to cut our ties with the failed politicians of the past, and embrace a bright, new future for all of our people," he said in a USA Today op-ed.

Clinton premiered her closing ad, saying that Americans are choosing whether the U is "dark and divisive or hopeful and inclusive".

"I love this country, and I'm convinced our best days are still ahead of us if we reach for them together," she says in the two-minute spot, speaking to the camera directly. It will air in prime time on NBC and CBS, a campaign official said.

Trump at the weekend released his own two-minute ad, an "argument for America," that his campaign said was backed by US$4 million.

The Republican nominee in the ad decried "a global power structure that is responsible for the economic decisions that have robbed our working class, stripped our country of its wealth and put that money into the pockets of a handful of large corporations and political entities".

The commercial showed images of billionaire George Soros, Federal Reserve Chair Janet Yellen, and Goldman Sachs Group Inc. CEO Lloyd Blankfein.

The Anti-Defamation League said the ad touched "on subjects that anti-Semites have used for ages".