WASHINGTON (CNN) -- A roller-coaster ride of an election campaign, buffeted by a superstorm and missteps on both sides, finally concludes Tuesday when America decides if President Barack Obama gets a second term or Republican challenger Mitt Romney will move into the White House in January.
In a contest reflecting the nation's deep political chasm, Obama and Romney ran dead even in final polls that hinted at a result rivaling some of the closest presidential elections in history.
The first polling results of the day in New Hampshire's Dixville Notch did nothing to change that notion. It was a tie.
President Barack Obama and his Republican rival, Mitt Romney, each received five votes.
The town in the state's northeast corner has opened its polls shortly after midnight each election day since 1960 - but Tuesday's draw was the first in its history.
Tuesday's outcome will influence the direction of a government and country facing chronic federal deficits and debt as well as sluggish economic growth in the wake of a devastating recession and financial industry collapse that confronted Obama when he took office as the first African American president in January 2009.
Voters also will determine the makeup of a new Congress, choosing all 435 members of the House of Representatives and 33 of the 100 senators. Analysts expect Republicans to maintain control of the House and Democrats to keep their narrow advantage in the Senate.
No matter who wins the presidency, the White House and Congress will face fresh pressure to legislate a comprehensive deficit reduction deal that has been stymied so far by intransigence on the issue of tax reform, with Republicans refusing to consider any kind of tax increase while Obama and Democrats insist on at least the wealthy paying a higher income tax rate.
Despite the building drama toward Election Day in the campaign expected to cost $2.6 billion, much of the outcome already was known.
Only a handful of states were considered up for grabs and both candidates and their campaigns concluded an exhausting final sprint through them over the weekend and on Monday.
The barnstorming amounted to a montage of Americana electioneering, with Obama and Romney shouting themselves hoarse before boisterous crowds, joined by top surrogates and star power such as Bruce Springsteen singing for Obama and Kid Rock for Romney.
In their final speeches, the candidates and their respective running mates -- Vice President Joe Biden and GOP Rep. Paul Ryan of Wisconsin -- blended inspirational visions for a better future with well-honed attacks in hopes of ensuring their committed supporters actually cast ballots while trying to coax votes from anyone still undecided.
Obama, Romney make final pitches
Obama briefly waxed nostalgic at his first event on Monday in Madison, Wisconsin, referring to Springsteen when he said: "I get to fly around with him on the last day that I will ever campaign, so that's not a bad way to end things."
He cited accomplishments of his first term, including ending the war in Iraq, winding down the war in Afghanistan, passing health insurance and Wall Street reforms, and ending the "Don't Ask, Don't Tell" policy that banned openly gay and lesbian personnel from the military.
"I know what real change looks like," the president said, referring to what he characterizes as Romney's false claim of being an agent of needed change. "You've got cause to believe me because you've seen me fight for it and you've seen me deliver it. You have seen the scars on me to prove it. You have seen the gray hair on my head to show you what it means to fight for change. And you've been there with me. And after all we've been through together we can't give up now because we've got more change to do."
Emotion overtook the president at the end of the day.
His eyes welled with tears as he thanked the people "who've given so much to this campaign over the years," during a stop in Des Moines, Iowa -- a place where his first campaign gained an early foothold in his first run for the White House.
"You took this campaign and made it of your own and you organized yourselves block by block, neighborhood by neighborhood, county by county, starting a movement that spread across the country," Obama said wiping away away tears three times as he talked.
In North Carolina, first lady Michelle Obama exhorted voters to endure the expected long lines to vote on Tuesday, telling a Charlotte crowd: "Once you are in that line, do not get out. Don't get out. And the waits could be long. We need you to wait it out."
For his part, Romney called Obama's record one of underachievement and failure, telling a cheering Virginia crowd at his second stop of the day that "almost every measure he took hurt the economy, hurt fellow Americans."
At an earlier event in Florida, Romney asked if people wanted four more years like the last four, raising the specter of continuing gridlock in Washington and adding that "unless we change course, we may be looking at another recession."
He promised to repeal the health care and Wall Street reforms of the Obama presidency and to "limit government rather than limiting the dreams" of Americans.
"We have known many long days and some short nights and now we are close. The door to a brighter future is open. It is waiting for us. I need your vote. I need your help. Walk with me. Tomorrow we begin a new tomorrow," Romney said.
Romney also planned two Election Day stops to continue campaigning until polls close. He'll visit Ohio -- considered the most vital swing state with 18 electoral votes -- and Pennsylvania, where Obama leads but the Romney campaign hopes for a late surge to grab the 20 electoral votes available.
It takes 270 of the 538 total electoral votes to win the presidency.
While both campaigns sought to project confidence in victory, the possibility loomed that neither candidate will get more than 50% of total votes cast. In a less likely but mathematically possible result, a tie in the Electoral College could occur, which would set up a congressional vote to break the deadlock.
As the challenger, Romney sought to frame the election as a referendum on Obama's presidency and to capitalize on his own background as multimillionaire businessman by depicting himself as better able to handle economic issues identified by voters as their biggest concern. His campaign stump speech hammered Obama over high unemployment and what he called excessive taxes and regulations that Romney said stifled faster growth.
Obama and his team attacked Romney's politics and his background as a venture capitalist, saying he would back policies favoring the wealthy over the middle class and exacerbate the already widening income and opportunity disparity in the country. The president wanted the race to come down to competing visions for the future and his oft-repeated goal of restoring the promise of the American dream of equal opportunity for all.
In particular, Obama repeatedly noted he backed a taxpayer bailout that helped restore General Motors and Chrysler while Romney opposed it. The issue, resonated in auto industry states like Michigan and Ohio, which was considered the most significant of the battlegrounds in the final days of the race.
Campaign chess match
Aside from the policy differences, the election amounted to a campaign chess match targeting specific states and demographic groups as part of plan to create a path to 270 electoral votes. Polling portrayed a race that hinged on the social and democratic divides in American society, with Obama supported most strongly by women, minorities and young respondents, while Romney did better among wealthy and middle class white men, from senior citizens down to 30 year olds.
In response, Obama emphasized the anti-choice positions of Romney and conservatives on abortion, their stance against gay rights and their opposition to providing a path to legal status for undocumented immigrants.
Re-election offered Obama, 51, the chance to secure a two-term legacy and seek further reforms he promised in his historic campaign of 2008 but was unable to deliver in the first four years. In particular, he has made comprehensive immigration reform a top target, as well as a deficit reduction plan that ends tax breaks for income over $250,000.
However, the wave of optimism that carried to him to victory in 2008 seemed muted four years later, with former supporters angered by the failure to achieve the kind of change in Washington they believed Obama had promised but failed to deliver. Particular issues of discontent included Obama's expanded use of unmanned drones to attack terrorist targets abroad, the lack of broad immigration reform and the continued existence of the federal Defense of Marriage Act that defines marriage as between a man and a woman.
For Romney, a multimillionaire businessman seeking to become the nation's first Mormon president, the election concluded a six-year quest for the presidency to achieve the office that his father -- former Michigan Gov. George Romney -- briefly and unsuccessfully sought in 1968.
Mitt Romney also failed in his first bid for the Republican nomination in 2008, then spent the next two years preparing for a second run that began in 2011 with a grueling primary campaign featuring a record 20 debates.
A former governor of moderate Massachusetts, he shifted to the right for the primary race to overcome a broad field that included former House Speaker Newt Gingrich, former Pennsylvania Sen. Rick Santorum, Rep. Michele Bachmann of Minnesota, Texas Gov. Rick Perry, former U.S. Ambassador to China Jon Huntsman and businessman Herman Cain.
Romney, 65, declared himself "severely" conservative and adopted stances against abortion, gay marriage and a path to legal residency for undocumented immigrants while also opposing higher tax rates as part of a deficit reduction plan. His support remained steady -- though well below a majority -- throughout the primary campaign while opponents dropped out one by one until Romney emerged as the winner and claimed the nomination at the GOP convention in late August.
However, his campaign endured a tough September, due in part to some unforced errors. A secretly recorded video from a May fundraiser became public, showing Romney referring to 47% of the country as dependent on government handouts and therefore unreachable to him as a candidate.
When U.S. diplomatic compounds came under attack on September 11, including an assault that killed the U.S. ambassador and three other Americans in Benghazi, Libya, Romney quickly issued a statement that was criticized for mistaken information and seeking to politicize a sensitive national security issue.
Then, in the first presidential debate on October 3, Romney began an energetic shift back to the political center and scored a clear victory over Obama by presenting himself as more moderate than the right-wing zealot portrayed by the president. He acknowledged the need for government regulation, opposed deporting undocumented immigrants and generally backed Obama's positions on the war in Afghanistan, the conflict in Syria and other foreign policy matters.
Obama's lackluster showing in the first debate contributed to an overwhelming consensus among analysts and poll results that Romney carried the night, and he began rising in the polls to erase what had been a consistent Obama lead since the conventions a month earlier. Stronger performances by Obama in the second and third debates began to slow Romney's momentum, though the Romney team claimed a surge put states like Michigan and Pennsylvania back in play. They were previously thought safe for the president.
With polls tightening in the final weeks, Romney or his surrogates heightened their attacks on key issues, including a campaign ad that implied the auto bailout led to shifting
The production of iconic Chrysler Jeeps to China. The automaker joined the Obama campaign in complaining that the ad was misleading, and the president said it was intended to scare workers for political gain.
However, the biggest impact on the end of the campaign was Superstorm Sandy, which blasted the East Coast from Maryland to Connecticut just over a week before Election Day. Obama and Romney canceled campaign events, and the president shifted to full emergency response mode as the storm and its devastation dominated the national focus for much of the final full week of campaigning.
An enduring image of the aftermath was Obama touring the storm damage with New Jersey Gov. Chris Christie, a Republican and top surrogate for Romney. The image and Christie's praise for Obama's handling of the crisis undermined a major Romney argument that the president valued personal gain over the good of the nation.
Final polls indicated Obama inching ahead nationally and in most of the battleground states, though the race remained too close to call.
"The hurricane is what broke Romney's momentum," Haley Barbour, the former Republican governor of Mississippi, told CNN on Sunday.
On the ground, record numbers of voters cast early ballots as both sides boasted of ramped-up organizations to identify and contact supporters. At the same time, Democrats complained that Republican-led state governments passed tighter voter registration laws in an effort to suppress minority turnout.
Overall, the total cost of the election for president and Congress could top a record-breaking $6 billion, according to the nonpartisan Center for Responsive Politics. The figure covers spending from January 2011 through whatever totals emerge after Tuesday's election.
Outside groups accounted for the biggest boost in spending, with independent organizations dropping more than $970 million. The increase was largely related to the 2010 U.S. Supreme Court ruling that paved the way for super PACs to raise and spend unlimited amounts of money as long as they did not coordinate with the campaigns.
CNN's Ed Payne, Ashley Killough, Rachel Streitfeld, Shawna Shepherd, Jim Acosta, Robert Yoon and Halimah Abdullah contributed to this report.