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Obama's victory speech included a heartfelt thank you to First Lady Michelle Obama and daughters Sasha and Malia.
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President Barack Obama won a second term on Tuesday, emerging from a long, punishing, and exorbitant campaign with a new mandate to lead a divided and anxious nation.
"Tonight in this election, you, the American people, reminded us that while our road has been hard, while our journey has been long, we have picked ourselves up," Obama said in a victory speech in his hometown of Chicago. "We have fought our way back and we know in our hearts for the United States of America, the best is yet to come."
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Obama said he was determined, inspired and still full of hope.
"Our economy is recovering. A decade of war is ending. A long campaign is now over," Obama said. "And whether I earned your vote or not, I have listened to you. I have learned from you. And you've made me a better president. And with your stories and your struggles, I return to the White House more determined and more inspired than ever about the work there is to do and about the future and life ahead."
But the cold reality is that when he arrives back in Washington, the president will face the same obstacles he did before the election. With Republicans maintaining control of the House of Representatives, the era of divisive partisanship will likely continue.
That challenge was articulated by one of his most outspoken opponents, Mitch McConnell, leader of Senate Republicans.
"Now it's time for the President to propose solutions that actually have a chance of passing the Republican-controlled House of Representatives and a closely-divided Senate, step up to the plate on the challenges of the moment, and deliver in a way that he did not in his first four years in office," McConnell said.
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Obama's triumph unfolded incrementally Tuesday night, as he racked up a string of victories in crucial battlegrounds. One after another, states that had been deemed toss-ups before Election Day fell into the president's hands.
Pennsylvania. Wisconsin. New Hampshire. Iowa. With each Obama win, the path to victory for his opponent, former Massachusetts Gov. Mitt Romney, got narrower.
Finally, just after 11 p.m. ET, NBC News projected Obama to win Ohio, his so-called "firewall" and the one state that has sided with the winning presidential candidate in every election since 1960. Obama's win there, thanks in large part to the state's support of his bailout of the auto industry, handed him the Electoral College swing votes he needed.
Romney conceded the race in a phone call to the president just before 1 a.m. ET. He then took the stage at the Westin Boston Waterfront Hotel, telling supporters that he wished the president well.
"This is a time of great challenges for America, and I pray that the president will be successful in guiding our nation," Romney said.
Obama's battleground victories were so authoritative that Florida, which was considered the biggest prize, wasn't even a factor.
Florida was the only state that remained too close to call as of 2:30 a.m. ET. Its results won't be known until after the start of business Wednesday.
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So many people turned out to vote Tuesday that Ohio, Florida and Virginia kept polls open after closing to accommodate the people who waited in long lines that snaked from the doors of polling places.
Exit polls indicated that Obama was favored among women, young adults, singles and Latinos - the last group by wider margin than in 2008.
"Today is the clearest proof yet that, against the odds, ordinary Americans can overcome powerful interests," Obama wrote in an email to supporters.
Obama, Romney and their proxies spent nearly $2 billion, a record amount for a presidential campaign.
In his concession speech, Romney said he had no regrets, and that he hoped that the country would move past its partisan differences to solve the nation's problems.
"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."
Less than an hour later, at about 1:45 a.m. ET, Obama appeared before a roaring crowd at the McCormick Place convention center in Chicago. His wife, Michelle, and their two daughters accompanied him on stage while Stevie Wonder's "Signed, Sealed, Delivered" blasted. Then they left him to deliver his victory speech.
Obama congratulated Romney "on a hard-fought campaign."
"We may have battled fiercely, but it's only because we love this country, we care so strongly about its future," he said.
The president went on to say that the rancor and rift that characterized the campaign was understandable, given the nation's challenges.
"That won't change after tonight. And it shouldn't. These arguments we have are a mark of our liberty, and we can never forget that as we speak, people in distant nations are risking their lives right now just for a chance to argue about the issues that matter, the chance to cast their ballots like we did today."
Obama, 51, the country's first black president, won election in 2008 on a promise of hope and change, but he triumphed this time with a starkly different message: asking voters to stick with him as he continues trying to fix the economy and improve America's standing in the world.
He defeated Romney, 65, a wealthy venture capitalist who'd been running for president for the better part of a decade. A win for Romney would have been vindication, of sorts, for his family; his father, George, ran unsuccessfully for the Republican presidential nomination in 1968.
The 2012 race highlighted two contrasting visions of the country. Where Romney emphasized the need to lower taxes, relax federal regulations and cut government spending, Obama promised to raise taxes on the wealthiest Americans and deploy government's help in pulling the country out of the economic doldrums.
Despite his image as stiff and disinterested in the plight of the middle class, Romney managed to make the race close by appealing to many voters' disappointment in Obama, and widespread anxiety about the economy. Romney promised to bring a businessman's sensibility to the job, a point he drove home in his first presidential debate, which he dominated. That performance sparked a surge in the polls that made the race tight right up until Election Day.
But Romney, in the end, was not able to fully convince an edgy public that he could do a better job than Obama. Nor was Romney able to overcome Obama's image as a more likable guy.
Now Romney may well have run his last race for public office.
Obama will begin his second term no longer a symbol of political catharsis, but as a flawed but adaptive leader who took a lot of lumps and learned from them.
The president's re-election means there will likely be no overturning of his signature domestic policy achievement, a health care reform law known as Obamacare. Obama has also promised to raise taxes on those earning more than $250,000 a year.
Obama must also make good on his campaign promises to finally correct America's economic path by finding ways to add a million more manufacturing jobs; boost domestic energy production, including a doubling the use of wind, solar, "clean coal " and natural gas; take money saved from troop withdrawals in Iraq and Afghanistan to invest in infrastructure back home; drastically reduce the county's carbon footprint; save Medicare; cut college loan costs; and slash the national deficit by $4 trillion.
When he returns to the White House, he won't have much time to savor his victory, because, he'll have to negotiate out of a year-end "fiscal cliff," when a series of tax cuts expire and massive government spending cuts go into effect.
As he noted in his email to supporters Tuesday night: "There's a lot more work to do."
