“It all comes down to you, it is out of my hands now, it is in yours,” a hoarse, moist-eyed Obama told a 20,000-strong crowd in Iowa, concluding his re-election bid in the state that nurtured his White House dream from 2007.
The foes, drained by fatigue, had earlier charged through the swing states that will decide the race, taking final shots hours before polls open in an election that will decide whether Obama wins a second White House term.
Obama, barnstorming with rock legend Bruce Springsteen and rapper Jay-Z, pleaded with supporters in Madison, Wisconsin to stick with him in a final push to the finish, as polls showed him as a slight favourite on Tuesday.
“If you’re willing to work with me again, and knock on some doors with me, make some phone calls for me, turn out for me, we’ll win Wisconsin. We’ll win this election. We’ll finish what we started,” he said.
Obama, who also visited Ohio on the final day, is hoping to defy historic precedents suggesting that presidents who preside over shaky economies and high unemployment fail to win re-election.
In what was, win or lose, his last campaign rally, Obama was wistful and striking many of the emotional chords that resonated through his campaign in 2008 but have been absent this time, following his crisis-strewn presidency.
“I came back to ask you to help us finish what we started because this is where our movement for change began, right here,” Obama said.
“After all we’ve fought through together, we cannot give up on change now. We know what real change looks like.”
After wrapping up in Iowa, Obama headed home to Chicago for election day.
Election eve polls cemented the impression that Obama has the slightest of leads but cannot take victory – and the historical validation of re-election – for granted.
Final national polls showed an effective tie, with either Romney or Obama favoured by a single point in most surveys, reflecting the polarised politics of a deeply divided nation.
Obama, however, led by three points in national polls conducted by Pew Research and by the Washington Post and ABC News, suggesting that if either candidate could boast of 11th-hour momentum, it was the 44th US president.
His last line of defence in the industrial Midwest also seemed to be holding: Obama led the RealClearPolitics.com average of polls in crucial Ohio by 2.9 percent, and was up by 2.4 points and 4.2 points in Iowa and Wisconsin.
Should those polls be reflected in vote totals on Tuesday, Obama would become only the second Democrat, after Bill Clinton, to win a second four-year term since World War II.
Obama’s team however, cheered by early vote data and the neighbourhood-by-neighbourhood political machine the president has assembled, insisted that they would be vindicated by the election.
“We’re going to win the electoral vote and we’re going to win the popular vote,” said Obama’s political guru David Axelrod.
“It’s going to be a close election as we always said. This is the season for weird theories, but we’re very, very confident of both those things.”
Springsteen told an 18,000-strong crowd in Wisconsin that his life in music had been dedicated to charting the distance between the American dream and American reality.
“Our vote tomorrow is the one undeniable way we get to determine the distance in that equation,” said The Boss, who was travelling with Obama aboard Air Force One.
Obama’s campaign deployed former president Bill Clinton to Pennsylvania, ostensibly a safe Democratic state but one which has seen a late run by Romney – evidence, according to Obama’s team, of desperation.
“I’m for President Obama because … he’s got a much better plan for the future,” said Clinton, who has overcome acrimony left over from Obama’s 2008 primary defeat of his wife Hillary to embrace the president.