Romney, who grew wealthy in business and ran the 2002 Olympic Games in Salt Lake City before entering politics, spoke only briefly to supporters, some of whom wept.
"I so wish that I had been able to fulfill your hopes to lead the country in a different direction," he said. "But the nation chose another leader and so Ann and I join with you to earnestly pray for him and for this great nation."
Moments later, Obama stepped before a far different crowd hundreds of miles away.
"Tonight you voted for action, not politics as usual," he said. He pledged to work with leaders of both parties to help the nation complete its recovery from the worst recession since the Great Depression.
Boehner issued a statement of his own, noting that while Obama won, so, too, did his House Republicans "If there is a mandate, it is a mandate for both parties to find common ground and take steps together to help our economy grow and create jobs, which is critical to solving our debt," he said.
By any description, the list of challenges is daunting - high unemployment, a slow-growth economy, soaring deficits, a national debt at unsustainable. To say nothing of the threat of a nuclear Iran and the menace of al-Qaida and other terrorist groups more than a decade after the attacks of Sept., 11, 2001.
There was no doubt about what drove voters to one candidate or the other in the presidential race.
About 4 in 10 said the economy is on the mend, but more than that said it was stagnant or getting worse more than four years after the near-collapse of 2008. The survey was conducted for The Associated Press and a group of television networks.
In the battle for the Senate, Elizabeth Warren turned Republican Scott Brown out of office in Massachusetts, and Rep. Joe Donnelly captured a seat from GOP hands in Indiana.
Deb Fischer picked up a seat for Republicans in Nebraska, defeating former Sen. Bob Kerrey.
In Maine, independent former Gov. Angus King was elected to succeed retiring GOP Sen. Olympia Snowe. He has not yet said which party he will side with, but Republicans attacked him in television advertising during the race, and Democrats rushed to his cause.
In the presidential race, Obama won in the reliably Democratic Northeast and on the West Coast. Pennsylvania was his, too, despite two late campaign stops by Romney.
Romney won most of the South as well as much of the Rocky Mountain West and Farm Belt.
The president was in Chicago as he awaited the voters' verdict on his four years in office. He told reporters he had a concession speech as well as victory remarks prepared. He congratulated Romney on a spirited campaign. "I know his supporters are just as engaged, just as enthusiastic and working just as hard today" as Obama's own, he added.
Romney reciprocated, congratulating the man who he had campaigned against for more than a year.
Earlier, he raced to Ohio and Pennsylvania for Election Day campaigning and projected confidence as he flew home to Massachusetts. "We fought to the very end, and I think that's why we'll be successful," he said, adding that he had finished writing a speech anticipating victory but nothing if the election went to his rival.
Like Obama, Vice President Joe Biden was in Chicago as he waited to find out if he was in line for a second term. Republican running mate Paul Ryan was with Romney in Boston, although he kept one eye on his campaign for re-election to the House from Wisconsin, a race he won.
The long campaign's cost soared into the billions, much of it spent on negative ads, some harshly so.
In a months-long general election ad war that cost nearly $1 billion, Romney and Republican groups spent more than $550 million and Obama and his allies $381 million, according to organizations that track advertising.
According to the exit poll, 53 percent of voters said Obama was more in touch with people like them, compared to 43 percent for Romney.
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