Army Pfc. Bradley Manning, center, steps out of a security vehicle as he is escorted into a courthouse in Fort Meade, Md., Wednesday, Nov. 28, 2012, for a pretrial hearing. Manning is charged with aiding the enemy by causing hundreds of thousands of classified documents to be published on the secret-sharing website WikiLeaks. (AP Photo/Patrick Semansky)

FILE - This June 7, 2012 file photo shows U.S. Ambassador to the U.N. Susan Rice listening during a news conference at the UN. Republican opposition to Rice's possible nomination to be secretary of state began to crack Sunday, Nov. 25, 2012, as Sen. John McCain said she was "not the problem" in the White House's explanation about the Sept. 11 attack in Libya and he could be persuaded to swing behind her potential promotion. McCain's comments provide an opening for the administration, which struggled mightily in the weeks leading up to the Nov. 6 election to tamp down speculation of a cover-up involving the attack against the U.S. Consulate in Benghazi. (AP Photo/Bebeto Matthews)