“If President Obama trusts him, I think Senator Hagel has the experience. He’s certainly got the qualities as a person,” said McChrystal, the former top U.S. commander in Afghanistan who resigned in 2010. “I think that level of trust and relationship between those people and with other members of the cabinet are the most important thing.”

Brennan has served as Obama’s chief counterterrorism adviser since 2008.

“John Brennan’s career of service and extraordinary record has prepared him to be an outstanding director of the CIA. ... Brennan has the full trust and confidence of the president,” the senior admin official

“For four years, he has seen the president every day, and been by his side for some of his toughest decisions - including the decision to launch the bin Laden raid,” the official added.