Two
current officials said another candidate is Mike Vickers, the Pentagon's assistant secretary for special operations. But a Defense Department official said Vickers has not been contacted for an interview. All the officials spoke on condition of anonymity because a replacement for Blair has not been announced.
Clapper currently is defense undersecretary for intelligence.
President Barack Obama was already talking to candidates for national intelligence director's job before Blair resigned Thursday under pressure from the White House.
Obama spokesman Robert Gibbs said the president had spoken with a number of well-qualified candidates so he could have people ready in case he decided to make a change with the intelligence post. Gibbs wouldn't comment on what candidates the president has spoken with, but said an announcement will come soon.
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Blair resigned after a tumultuous 16-month tenure that critics say underscored the disorganization inside the Obama administration's intelligence apparatus. A spate of high-profile attempted terror attacks that revealed new national security lapses has rocked the White House over the past six months.
Gibbs was publicly supportive of Blair Friday, commending him for increasing the government's focus on counterterrorism and radicalization, particularly in Afghanistan and Southeast Asia. Still, he said the president believed it was time to make a change.
"There is probably no harder job in Washington, besides being president, than being director of national intelligence," he said. "The president simply believed that it was time to transition to a different director."
Blair is the third person to hold the director of national intelligence job, which is to oversee the nation's 16 intelligence agencies. The post was created in response to the failure to prevent the Sept. 11, 2001 terrorist attacks.
But Blair's tenure highlighted the flaws that still exist in coordinating intelligence. Following an attempted bombing aboard a plane on Christmas Day, a Senate Intelligence Committee found that the National Counterterrorism Center could have prevented the incident. As director of national intelligence, Blair oversaw the center.
Gibbs said the Intelligence Advisory Board, which advises the president on the effectiveness of the intelligence community, has made recommendations for possible changes to the structure of the director of national intelligence post.
Gibbs said Blair's resignation will be effective next Friday. Deputy National Intelligence Director David Gompert will become acting director until a permanent replacement is named.