Voters head to polls to give verdict in presidential race

We know what change looks like

Obama focused on Wisconsin, Ohio and Iowa, the three Midwestern swing states that, barring surprises elsewhere, would give him 270 electoral votes. Romney visited the must-win states of Florida, Virginia and Ohio before finishing in New Hampshire, where he launched his presidential run in June 2011.

After two days of nearly round-the-clock travel, Obama wrapped up his final campaign tour in Des Moines, Iowa, with a speech that hearkened back to his 2008 campaign.

"I've come back to Iowa one more time to ask for your vote. I came back to ask you to help us finish what we've started, because this is where our movement for change began," he told a crowd of some 20,000 people.

Obama's voice broke and he wiped away tears from his eyes as he reflected on those who had helped his campaign.

Romney's final day included stops in Florida, Virginia, Ohio and New Hampshire. The former governor of Massachusetts ended the day at a raucous "Final Victory" rally in Manchester, New Hampshire, the city where he launched his campaign last year.

"We're one day away from a fresh start. We're one day away from a new beginning," the candidate, sounding hoarse at his fifth rally of the day, told the crowd of 12,000 at a sports arena in the center of the city.

Obama ridiculed Romney's claims to be the candidate of change and said the challenger would be a rubber stamp for a conservative Tea Party agenda.

"We know what change looks like, and what he's selling ain't it," he said in Columbus, Ohio.

Romney argued he was the candidate who could break the partisan gridlock in Washington, and said four more years of Obama could mean another economic recession.

"His plan for the next four years is to take all the ideas from the first term - the stimulus, the borrowing, Obamacare, all the rest - and do them over again," he said in Lynchburg, Virginia.

The common denominator for both candidates was Ohio, the most critical of the battlegrounds, particularly for Romney. Without the state's 18 electoral votes, the path to victory becomes very narrow for the Republican.

Polls have shown Obama with a small but steady lead in the state for months, sparked in part by his support for a federal bailout of the auto industry, which accounts for one of every eight jobs in Ohio, and by a strong state economy with an unemployment rate lower than the 7.9 percent national rate.

That undercut the central argument of Romney's campaign - that his business experience made him uniquely qualified to create jobs and lead an economic recovery.

Obama fought back through the summer with ads criticizing Romney's experience at the equity fund Bain Capital and portraying him as out of touch with ordinary Americans.

That was part of a barrage of advertising in the most heavily contested battleground states from both candidates and their party allies, who raised a combined $2 billion.

The rise of "Super PACs," unaffiliated outside groups that can spend unlimited sums on behalf of candidates, also helped fuel the record spending on political ads that swamped swing-state voters.

Romney planned to vote at home in Massachusetts in the morning before a final trip to Ohio and Pennsylvania, a Democratic-leaning state that he has tried to put in play in recent weeks.

Obama, who voted in October, will spend the day at his home in Chicago.

The two candidates took a break from campaign rallies to tape interviews that aired during halftime of Monday Night Football, a U.S. television institution.

Romney said the New England Patriots were his favorite football team and jokingly said that, as a former Massachusetts governor, he to MORE