Former Massachusetts Gov. Mitt Romney campaigns at Ring Power Lift Trucks in Jacksonville, Fla., on Monday. Polls show him widening his lead in Florida after adopting a more aggressive campaign style. Charles Dharapak/AP hide caption

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President Obama waves after speaking at a UPS facility in Las Vegas on Thursday. Nevada is one stop on the president's latest road trip focusing on the economy. Julie Jacobson/AP hide caption

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Newt Gingrich arrives for a GOP presidential candidate forum Saturday in South Carolina. Gingrich had to be reminded of the rules not to mention rivals by name, but was still able to continue criticism of Mitt Romney. Joe Raedle/Getty Images hide caption

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Mitt Romney speaks during a Chamber of Commerce breakfast Monday in Nashua, N.H. Justin Sullivan/Getty Images hide caption

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Former Massachusetts Gov. Mitt Romney pleaded with his supporters at a rally Monday in Dubuque, Iowa, saying, "I need every vote." He did — winning the Iowa caucuses the next day by just eight votes. Chip Somodevilla/Getty Images hide caption

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Former Massachusetts Gov. Mitt Romney greets voters after speaking at the Mississippi Valley Fairgrounds on Wednesday in Davenport, Iowa. Win McNamee/Getty Images hide caption

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President Obama, Vice President Joe Biden and members of his National Security team receive an update on the mission against Osama bin Laden in the Situation Room of the White House. A classified document seen in this photograph has been obscured. Pete Souza/White House hide caption

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Republican presidential candidate Newt Gingrich greets local residents after speaking at the Willow Ridge Golf Course on Dec. 15 in Fort Dodge, Iowa. Charlie Neibergall/AP hide caption

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On this April 7, 2009, visit to Iraq, President Obama greets U.S. troops at Camp Victory in Baghdad. On Dec. 2, 2011, the base was handed over to the Iraqi government. All U.S. soldiers are to be gone from Iraq by year's end. Charles Dharapak/Associated Press hide caption

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White House press secretary Jay Carney speaks Monday during his daily press briefing, as a clock counting down the expiration of the payroll tax cut benefit looms in the background. Alex Wong/Getty Images hide caption

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Ornaments made to honor loved ones decorate the Gold Star Families Tree. Jim Watson/AFP/Getty Images hide caption

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