Who will be Romney's VP? The naming of his running mate is likely going to come in mid-August, after his foreign trip and the conclusion of the Olympics. Ken Rudin collection hide caption

itoggle caption Ken Rudin collection

Vice President Joe Biden is interviewed by NPR's Robert Siegel in the Secretary of War Suite of the Eisenhower Executive Office Building, Dec. 13. David Lienemann/The White House hide caption

itoggle caption David Lienemann/The White House

Vice President Joe Biden smiles after filing papers for President Obama to be on the N.H. primary ballot. (AP Photo/Jim Cole)

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itoggle caption Jim Cole/AP