Senator Chuck Hagel (R-NE) leaves a news conference in Omaha, Nebraska in this March 12, 2007, file photo. President Barack Obama is expected to announce his nominees for secretaries of state and defense in the next two weeks, with former Republican senator Hagel on the short list of potential choices to head the Pentagon, senior administration officials said on December 4, 2012. REUTERS/Dave Kaup/Files (UNITED STATES – Tags: POLITICS ELECTIONS)