The Senate has recently confirmed two of Obama's cabinet nominees -- Jack Lew for Treasury and Chuck Hagel for Defense -- but his pick to lead the Central Intelligence Agency could continue to hit hurdles on his road to the Senate floor.
John Brennan's vote in the Senate Intelligence Committee was delayed last week and is now expected to happen on Tuesday.
He faces questions from members on both sides of the aisle. Democrats questioned him over the government's controversial interrogation and detention programs, as well as targeting of suspected terrorists. Republicans asked about leaks of secret information about counterterrorism activities and threatened to hold up his nomination as they sought more information on the Benghazi, Libya consulate attack which killed four Americans including a U.S. ambassador in September.