Vice President Biden is greeted by Rep. Gerald Connolly, D-Va., before speaking at a backyard rally for Virginia Democratic gubernatorial candidate Terry McAuliffe on Monday. Jacquelyn Martin/AP hide caption

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Vice President Biden at a December 2012 meeting of police chiefs on gun control, held in Washington, D.C. Carolyn Kaster/AP hide caption

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President Obama is officially sworn in Sunday by Chief Justice John Roberts in the Blue Room of the White House. Next to Obama are first lady Michelle Obama, holding the Robinson Family Bible, and their daughters, Malia and Sasha. Larry Downing/AP hide caption

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President Obama at the White House today, with Vice President Biden in the background. Mandel Ngan/AFP/Getty Images hide caption

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Vice President Biden and President Obama at the White House on Dec. 19. Biden has been charged with drawing up "concrete proposals" on how to reduce gun violence. Fang Zhe/Xinhua /Landov hide caption

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President Obama participates in an interview with Robin Roberts of ABC's Good Morning America in the White House on May 9. During the interview, Obama expressed his support for gay marriage, a first for a U.S. president. The White House/Getty Images hide caption

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