WASHINGTON (AFP) - Mrs Hillary Clinton and Mr Donald Trump sprinted from swing state to swing state in a fight for the last few unclaimed votes on Wednesday (Nov 2), six days out from an election that has set the world on edge.
Mrs Clinton is ahead in most polls, but a last-minute surge by the 70-year-old Trump has delighted US foes, nauseated allies and winded global financial markets.
In less than a week, Americans will chose between a populist Republican who shattered political norms and a scandal-tormented Democrat vying to be America's first female president.
The choice has left many US voters cold and made the outcome difficult to predict.
One ABC News/Washington Post tracking poll on Tuesday even gave Mr Trump a narrow lead.
The real estate mogul has been hit by scandal after scandal, accused of sexual assault, not paying taxes and having ties to Russia's President Vladimir Putin and the mob.
But renewed FBI scrutiny of Mrs Clinton's use of a private email server as secretary of state has excited Republicans and underlined public doubts about the Democrat's trustworthiness.
"Investors are jittery," said Mr Jack Ablin, chief investment officer for the BMO Bank, "market volatility has spiked."
Mr Trump's pledge to scrap the North America Free Trade Agreement and build a wall on the southern border has made the Mexican peso a barometer for the market's unease.
The unit has weakened against the dollar by almost four per cent in the last week alone.
Meanwhile stocks from New York to Tokyo swooned, wiping billions off investments and pensions.
Iran's supreme leader Ayatollah Ali Khamenei - whose regime survives by painting America as a comic-book foe - crowed that the "catastrophic reality" of the two candidates "goes beyond what even we were saying."
In Britain, a giant effigy of Mr Trump wielding the head of his rival Clinton was to be burned during traditional bonfire celebrations.
The long and often unedifying 2016 White House race is now being fought in a few corners of a few states.
Mr Trump, Mrs Clinton and their most prized surrogates have virtually taken up residence in Florida, Ohio and North Carolina.
The three states offer the best chance for both candidates to cross the winning threshold of 270 out of 538 electoral college votes.
But the two White House hopefuls are also placing some final long-shot bets.
Mrs Clinton will travel to Arizona, which Democrats haven't won since 1996 when her husband Bill claimed the presidency by a landslide.
An Emerson poll on Wednesday had Mrs Clinton losing the state by four percentage points. But both of its Republican US Senators have opposed Mr Trump, offering the tantalising prospect of a shock Clinton win.
Meanwhile Mr Trump has been campaigning in Wisconsin and Michigan, both traditionally Democrat states that polls show Mrs Clinton leading by six points or more.
And the reality TV star will spend most of on Wednesday in Florida, which is likely to make-or-break his presidential dreams.
Pollster TargetSmart forecast that Mrs Clinton could win Florida - and all but bar Mr Trump any route to the White House - by a massive eight point margin, 48 to 40 per cent.
The Florida poll, conducted with the College of William and Mary, used only a small sample of voters but targeted those who had already cast ballots under the state's early voting law.
An average of earlier Florida polls by tracker RealClearPolitics gives Mr Trump a narrow one point lead there, and TargetSmart's survey suggests many registered Republicans have switched camps.
But the tumultuous race may have a few twists left.
As they jet across the country, both candidates are also winding up to their final pitch to voters.
Mrs Clinton has spent each day of the final stretch targeting specific groups of voters - women, African-Americans, Latinos - the same coalition that carried President Barack Obama to office.
The popular outgoing president has told African-American fans that he would take it as a personal insult if they did not back Mrs Clinton.
"The African-American vote right is not as solid as it needs to be," Mr Obama told radio's Tom Joyner Morning Show, the first of a series of interviews he gave onWednesday before heading to North Carolina to press the case.
"I guarantee you he'll dig up Michelle's garden," Mr Obama said, warning that Mr Trump may destroy the White House vegetable patch cultivated by his even-more popular wife.
"You think I'm joking?" he asked.