"I know I look a little bit older, but I've got a lot of fight left in me," a raspy-voiced Obama said in New Hampshire alongside former president Bill Clinton, the onetime political foe who's become his loyal attack dog in recent weeks.
Clinton warmed up the crowd of 14,000 by taking repeated shots at Romney, mocking the Republican presidential hopeful's shifting policy positions by saying he'd make a good "chief contortionist at Cirque du Soleil."
Obama, for the most part, took a higher road, imploring his supporters to keep their eyes on the prize.
"If you're willing to work with me, if you're willing to stand with me, if you're willing to knock on some doors with me, if you're willing to make some phone calls with me, if you're willing to turn out for me, we'll win New Hampshire," he said. "We'll win this election."
In Iowa, Romney took aim.
"Talk is cheap," he said.
"But a record is real and it's earned with real effort. You can't measure change in speeches. You measure change in achievements .... Four years ago, the candidate Obama promised us to do an awful lot, he was going to do so much for us, but he failed very short of that."
Most public opinion polls have had Obama and Romney in a statistical tie nationally for weeks, but a new survey from the Pew Research Center released Sunday showed the president with a three-point lead over his rival.
His improved standing in the Pew poll — last week, the candidates were tied at 47 per cent in the same survey — was apparently fuelled by Obama's widely praised handling of the federal response to mega-storm Sandy. He's now leading Romney 48 to 45 per cent after almost 70 per cent of the Pew respondents, most of them in swing states, gave him high marks on Sandy.
Obama also maintains a slight edge in several battleground states that will determine the outcome of Tuesday's vote.
Nonetheless each campaign was projecting an air of confidence on Sunday. Top surrogates took to the talk-show circuit to insist their man had the momentum.
"I'm very confident that, two days out from election day, the president's going to be re-elected on Tuesday night," David Plouffe, a White House adviser who managed the president's 2008 campaign, told NBC's "Meet the Press."
Seven states, representing 89 electoral college votes of the 270 needed to win the White House, are considered battlegrounds: Colorado, Iowa, Wisconsin, Ohio, Virginia, Florida and New Hampshire. Nevada and North Carolina are also in play for both Obama and Romney.
"All these states right now, we think the president's in a good position to win," Plouffe said.
Republican Eric Cantor, a Virginia congressman and the majority leader of the House of Representatives, denied his state would go Democrat, as it did in 2008 for the first time since 1964.
"We're going to win this state, and I think we're going to win it a lot bigger than people are predicting," he said on "Meet The Press." "Here on the ground, there is a lot of enthusiasm for Mitt Romney and Paul Ryan."
It's Ohio, however, that's emerged the crown jewel in the race. No Republican has won the presidency without Ohio, and the path to victory becomes significantly more onerous for both Obama and Romney if they lose the so-called Buckeye State on Tuesday.
Both men were in Ohio on Sunday as a new Columbus Dispatch poll suggested the state was still up for grabs, with Obama ahead by just two percentage points.
Other polls have shown Obama with a bigger advantage in Ohio, but both candidates were nonetheless focused on the state, hoping to win over that slim but significant sliver of undecided voters who could seal their electoral fate.
Their 11th-hour campaigning comes after months of each man portraying the other as posing profound risks to the future health and prosperity of the United States.
Obama has been castigated by Republicans for a tepid economic recovery following the financial meltdown that took grim hold of the United States just as he won the White House in 2008.
They've also accused him of being a borderline socialist by advocating big government and a welfare state while raising taxes and running up the national debt to levels they consider obscene.
Obama, in fact, has cut taxes and shrunk government during his four years in office, slashing more than half a million federal jobs since 2009. And the billions he's spent in bailouts and economic stimulus measures are credited by many economists with preventing the U.S. from falling into the abyss of another Great Depression.
The president also faced an obstructionist Congress for the past two years. On the eve of the mid-term elections in October 2010, top Senate Republican Mitch McConnell said it was the party's "single most important" goal to deny Obama a second term.
Democrats, meantime, have warned Romney and his running mate, Paul Ryan, will slash cherished entitlement programs, including Medicare, and will loosen Wall Street regulations to the extent that another financial meltdown could result.
They also malign Romney for switching his stances on various issues.
The Obama campaign got a boost recently from the Washington Post when it published a scathing editorial branding Romney's campaign an "insult" to the intelligence of Americans.
"He was a friend of immigrants, then a scourge of immigrants, then again a friend. He was a Kissingerian foreign policy realist, then a McCain-like hawk, then a purveyor of peace. He pioneered Obamacare, he detested Obamacare, then he found elements in it to cherish," the Post wrote.
"Assault weapons were bad, then good. Abortion was okay, then bad. Climate change was an urgent problem; then, not so much. Hurricane cleanup was a job for the states, until it was once again a job for the feds."
Both politicians, meantime, have been criticized equally for failing to provide the American public with much by way of policy specifics over the course of the gruelling campaign that focused, for the most part, on the state of the U.S. economy.
If Obama manages to hold onto his slim leads in key swing states, he'll become the first incumbent president since Franklin D. Roosevelt to win a second term when unemployment was above 7.4 per cent.
A loss, meantime, would place him in the company of Gerald Ford, Jimmy Carter and George H. W. Bush as incumbents who lost the White House when the jobless rate was above seven per cent.
Tuesday's vote could represent another rarity in American politics: the victor could lose the popular vote while winning the election.
Throughout the course of U.S. history, only four presidents have managed the feat: John Quincy Adams in 1824, Rutherford B. Hayes in 1876, Benjamin Harrison in 1888 and George W. Bush in 2000.
Under the American political system, presidential hopefuls compete not for popular vote, but for the 270 electoral college votes up for grabs stateside. Those votes are assigned based on a state's population and representation in Congress.
California, a reliably Democratic state, has the most electoral college votes of any state in the union, with 55.
The spectre of 2000's recount was also fresh in the minds of both campaigns as the horse race drew to a close.
Twelve years ago, a clear victor didn’t emerge until more than a month after election day when the U.S. Supreme Court effectively handed the presidency to George W. Bush by putting the brakes on a Florida recount.
This election, thousands of lawyers from both presidential campaigns will descend upon polling stations in key battleground states on Tuesday to keep an eye on their opponents and launch legal action if necessary.
Among other things, they’ll be looking out for voter intimidation, how voters are instructed and how poll workers conduct themselves.