After months of candidates' sparring and billions of dollars of campaign spending, voters went to the polls Tuesday to decide a presidential race that has been defined by its intensity and razor-thin margins.
Barack Obama and Mitt Romney entered Election Day locked in a near-dead heat, with both candidates expressing confidence that their supporters would deliver a win. Ultimately, voters in a handful of battleground states will have the final say in what has been the most expensive presidential contest in history. Polls suggest that decision day could stretch into a long night.
Tuesday started with Vice President Joe Biden casting his ballot in Delaware. Mr. Romney and his running mate, Paul Ryan, were in their home states of Massachusetts and Wisconsin to vote, while Mr. Obama became the first president to vote early when he cast a ballot on Oct. 25.
Residents of two tiny villages in northern New Hampshire headed to the polls at midnight, casting the first Election Day votes in the nation. After 43 seconds of voting, President Barack Obama and Republican Mitt Romney each had five votes in Dixville Notch, the Associated Press reported.
In Hart's Location, Mr. Obama won with 23 votes. Mr. Romney received nine votes, and Libertarian Gary Johnson received two.
Mr. Obama is in Chicago on Election Day after making his final swing through tossup states on Monday. Mr. Romney, though, decided to fight on, adding last-minute stops in Ohio and Pennsylvania on Tuesday. The Republican nominee had been riding a wave of momentum after the first presidential debate, but polls show his rise tapering off and the president regaining his footing in recent days.
More than 30 million people already have cast ballots, but the two campaigns are counting on their ground game and a final, Election Day push to determine the winner.
The race was tight from the start. And now that nearly $3 billion has been funneled into attack ads, super-PAC expenditures and get-out-the-vote efforts, many polls show a contest that is too close to call. The final Wall Street Journal/NBC News survey of likely voters showed Mr. Obama leading by a hair, 48% to 47%.
Polls give the president a slight edge in several key battlegrounds, but many are within the margin of error and the race has tightened during the campaign's final weeks.
For both candidates, the goal is the same: accumulate 270 electoral votes. Mr. Obama appears to have more paths to reach that number, but Romney campaign officials point to the Republican nominee's strength with independent voters and the intensity of his support as evidence that Election Day could break his way.
With time running out Monday, both candidates called upon surrogates, spouses and rock stars to lend a hand on the campaign trail as they tried to squeeze several battleground states into a single day.
Mr. Romney's schedule suggested that his campaign would conclude with what was billed as a "final victory rally" with Kid Rock Monday evening in New Hampshire. But Monday afternoon, campaign officials announced that there was more to come, as Election Day events were added in Ohio in Pennsylvania.
The Republican nominee's fortune could turn on either of those two states. Ohio is as close to a must-win as any state for Mr. Romney. No Republican has secured the presidency without it. But during the last couple weeks, the Romney campaign has sketched an alternate path through Pennsylvania, a state that long has been considered Democratic-leaning.
Mr. Romney had largely bypassed the state until recently, when Republicans began spending time and money in Pennsylvania, arguing that the race there had narrowed and now was within reach. The Real Clear Politics' average of polls in the state still shows Mr. Obama with nearly a four-percentage-point advantage.
In Virginia Monday, Mr. Romney continued to cast himself as a change agent while arguing that the president would deliver four more years like the last four years.
"Accomplishing real change is not just something I talk about—it's something I've done," he said.
Mr. Romney also accused the president of passing blame to his predecessor.
"I'm not just going to take office on Jan. 20," he said. "I'm going to take responsibility for that office as well."
Mr. Obama made his closing argument Monday, and Bruce Springsteen provided the musical accompaniment for the president's last day on the trail. The singer and the president moved from one battleground to the next, making stops in Wisconsin, Ohio and Iowa.
Along the way, Mr. Obama touted his first-term accomplishments, telling supporters that jobs are being created, home values are on the rise, the war in Iraq is over and Osama bin Laden is dead.
"We've made progress these last four years," he said to the crowd in Madison, Wis. "But the reason we're all gathered here—in addition to listening to Bruce—is because we know we've got more work to do."
Mr. Obama described Mr. Romney as a talented salesman who is trying to repackage the "same old bad ideas" of the last Republican administration and rebrand them as change.
"We tried our ideas. They worked. The economy grew. We created jobs. Deficits went down," the president said. "We tried their ideas. They didn't work. The economy didn't grow, not as many jobs, and the deficit went up."
Mr. Obama wrapped up his campaign with a final rally in Des Moines, Iowa, the state in which he began his first presidential campaign. Iowa helped to propel him out of the caucuses toward the Democratic nomination and ultimately the White House. Mr. Obama will spend election night in Chicago. Mr. Romney was casting his ballot in Belmont, Mass., Tuesday morning and after appearing at rallies in Pennsylvania and Ohio, he will return to Boston Tuesday night.
As the campaign reached its frantic finish, both sides were girding for a battle that could extend beyond Tuesday. Legal wrangling over early voting and provisional ballots already has begun in Florida and Ohio. The emergence of legal challenges in Ohio and the fact that provisional ballots in the state won't be counted until 10 days after the election raised questions about whether this contest could go into overtime if the result hinges on the Buckeye State.