A contentious confirmation fight could send Rice into the job with weakened support and use up some of the tough votes he may need from allies in the Senate later. Still, Obama has already set a tone that he may choose Rice regardless.
A decision on new leadership for the CIA is not as urgent. That's partly because Acting Director Michael Morell is still dealing with the fallout of David Petraeus' resignation over an extramarital affair and the battles with lawmakers over the events that led to the death of four Americans in Libya.
Morell is highly respected within the administration and seen as a top contender.
Other candidates are the White House's top counterterrorism and homeland security advisor, John Brennan, and the Pentagon's top intelligence official, Undersecretary for Defense Intelligence Michael Vickers, a former CIA officer and Green Beret. Also possible is the former senator Hagel, should he miss out for the top Pentagon job. Hagel co-chairs Obama's intelligence advisory board and held senior positions on the Senate Intelligence and Foreign Relations committees.
A near-term shakeup at the Defense Department would come as the Pentagon faces a flurry of decisions on troop levels in Afghanistan and budgets. The looming end-of-the year spending cuts the White House and Congress are seeking to avert would hit the Pentagon particularly hard.
At Defense, Hagel would give Obama a whiff of bipartisanship, and could be the only Republican in the Cabinet if Transportation Secretary Ray LaHood leaves, as expected.
Flournoy would be the first woman to lead the Defense Department. She served in the Pentagon under Panetta as undersecretary of defense for policy, resigning early this year. She served as a foreign policy adviser to Obama during his re-election campaign.
Carter, who has served as deputy defense secretary for the past year, is a protege of former Defense Secretary William Perry.
Associated Press writers Kimberly Dozier, Lolita C. Baldor and Robert Burns contributed to this report.
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