On Monday President Obama nominated former Senator Chuck Hagel to the post of secretary of defense and current counterterrorism adviser John Brennan as director of the Central Intelligence Agency. Both nominees may run into problems getting confirmed to their positions by the Senate.

"I hope that the Senate will act on these confirmations promptly," the president said at a White House ceremony. "When it comes to national security, we don't like to leave a lot of gaps between the time that one set of leaders transitions out and another transitions in."

Hagel, who served three terms in the Senate as a Republican from Nebraska, could face a tough confirmation process. His past views and statements on Israel, Iran and gays in the military have generated some controversy, and some senators have expressed doubts about whether he could get the necessary votes to be confirmed. Hagel would succeed Leon Panetta as the head of the Pentagon.

In 2008 Brennan, a 25-year CIA veteran, withdrew from consideration as the spy agency's director due to his connection with Bush Administration-era "enhanced interrogation techniques." It is expected that that issue will return when the Senate begins deliberating his nomination. Brennan would replace David Petraeus, who resigned in November due to an extramarital affair; Deputy Director Mike Morell has been acting director the CIA since then.

Hagel and Brennan would continue the process of filling out Obama's second-term national-security team. John Kerry has already been nominated to fill Hillary Clinton's spot as secretary of state.

[Reuters, New York Times]