Sen. John Kerry, D-Mass., U.N. Ambassador Susan Rice, and Secretary of State Hillary Clinton listen to President Obama speak at the State Department in May 2011. With Rice withdrawing her name from consideration to succeed Clinton, speculation has turned to Kerry. Chip Somodevilla/Getty Images hide caption

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Secretary of State Hillary Clinton speaks following the death of Osama bin Laden, Monday, May 2, 2011. Jacquelyn Martin/ASSOCIATED PRESS hide caption

itoggle caption Jacquelyn Martin/ASSOCIATED PRESS

"One of those actions that is under review is a no-fly zone" in Libya, Secretary of State Hillary Rodham Clinton told the House Foreign Affairs Committee. J. Scott Applewhite/AP hide caption

itoggle caption J. Scott Applewhite/AP