President Obama walks with White House Chief of Staff Jack Lew on March 2 on the South Lawn of the White House. Mandel Ngan/AFP/Getty Images hide caption

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President Obama is introduced to the Business Roundtable by Boeing CEO Jim McNerney in Washington on Wednesday. Charles Dharapak/AP hide caption

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President Obama speaks at the National Defense University in Washington on Monday. Since his re-election four weeks ago, Obama is showing signs of a new, more aggressive leadership style. Charles Dharapak/AP hide caption

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Kay Bailey Hutchison of Texas and Jon Kyl of Arizona on Tuesday introduced a bill that would allow illegal immigrants to stay in the country, but would not offer them a path to citizenship. Alex Wong/Getty Images hide caption

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President Obama speaks during Veterans Day ceremonies at Arlington National Cemetery in Virginia on Sunday. Brendan Smialowski/AFP/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 new NPR poll shows the outcome of the Nov. 6 election is too close to call. Mitt Romney leads President Obama nationwide; Obama leads Romney in key battleground states. Both leads are within the poll'€™s margin of error. Pablo Martinez Monsivais/AP hide caption

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Libertarian Party presidential nominee Gary Johnson addresses students at Macalester College in St. Paul, Minn., in September. Jim Mone/AP hide caption

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Early voting has begun in the battleground states of Ohio, Virginia and Iowa. Voting booths were set up for early voting Thursday at the Black Hawk County Courthouse in Waterloo, Iowa. Ahead of Wednesday's first presidential debate, an NPR poll finds President Obama with a 7-point lead nationally, but his GOP challenger, Mitt Romney, is within striking distance. Scott Olson/Getty Images hide caption

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President Obama speaks at the Fox Theater in Oakland, Calif., on Monday. Saul Loeb/AFP/Getty Images hide caption

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Voter walk outside of a polling place at the First Baptist Church of Windermere, in Orlando, Fla., during the state's primary on Jan. 31. Matt Rourke/AP hide caption

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President Obama at a Democratic Party election fundraiser in Chicago on June 1. Jason Reed/Reuters/Landov hide caption

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Bill Clinton speaks with President Obama in the White House Briefing Room after a private meeting in the Oval Office in 2010. The former president has become Obama's highest-profile advocate this campaign season. Jim Watson/AFP/Getty Images hide caption

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President Obama is applauded after signing the health care overhaul during a ceremony in the White House on March 23, 2010. Then-Gov. Mitt Romney signs a Massachusetts health care overhaul at Faneuil Hall in Boston on April 12, 2006. Win McNamee/Boston Globe via Getty Images hide caption

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