Some of the faces of those who supported the president, at his victory rally Tuesday in Chicago. Jewel Samad /AFP/Getty Images hide caption

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Obama has become only the third U.S. president to win re-election by a narrower margin than his first victory. Having won a second term, Obama will seek to set the nation's agenda on issues ranging from taxes to immigration, but he may continue to struggle in selling his ideas to Congress. Robyn Beck/AFP/Getty Images hide caption

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President Obama walks on stage with first lady Michelle Obama and daughters Sasha and Malia to deliver his victory speech on election night in Chicago. Win McNamee/Getty Images hide caption

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President Obama's performance in the first presidential debate cost him a lot. Chip Somodevilla/Getty Images hide caption

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A worker installs carpet into a Jeep Liberty at the Toledo Assembly Complex in Toledo, Ohio, in 2011. J.D. Pooley/Getty Images hide caption

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President Obama holds a copy of "The New Economic Patriotism: A Plan for Jobs & Middle-Class Security," which outlines some of his agenda for a second term, during a rally in Richmond, Va., on Thursday. Chip Somodevilla/Getty Images hide caption

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A boat skims through the melting ice in the Ilulissat fiord, on the western coast of Greenland, in 2008. The glacier is the most active in the Northern Hemisphere, producing 10 percent of Greenland's icebergs, or some 20 million tons of ice per day. But experts say the glacier is in bad shape because of climate change. Steen Ulrik Johannessen/AFP/Getty Images hide caption

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Broward County canvassing board member Judge Robert Rosenberg examines a disputed ballot Nov. 24, 2000, in Fort Lauderdale, Fla. Wilfredo Lee/AP hide caption

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Onlookers listen as President Obama speaks Friday in Fairfax, Va., about the choice facing women in the election. Carolyn Kaster/AP hide caption

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Supporters turned out for President Obama's first post-debate rally on Oct.4 in Denver. The president is facing a fierce fight for Colorado after winning it by 9 points four years ago. RJ Sangosti/AP hide caption

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President Obama and former Massachusetts Gov. Mitt Romney participate in the second presidential debate at Hofstra University in Hempstead, N.Y., on Tuesday. Charles Dharapak/AP hide caption

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Republican presidential nominee Mitt Romney and President Obama spar over energy policy during the second presidential debate at Hofstra University on Tuesday. Charlie Neibergall/AP hide caption

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President Obama speaks to supporters last month during a campaign stop in Las Vegas. Isaac Brekken/Getty Images hide caption

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