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.
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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.
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Republican presidential candidate Mitt Romney, joined by Sen. Marco Rubio, R-Fla., talks to reporters during a news conference in Aston, Pa., on Monday. Rubio is frequently mentioned as a potential running mate for Romney.
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