Barack Obama's top priority will be appointing a Treasury secretary and White House chief of staff. The leading candidates: two Clinton administration stalwarts, Lawrence Summers and Rep. Rahm Emanuel.

It's unlikely the president-elect can assemble a Cabinet and staff within 10 days as some have advised, say people who have discussed this with him in recent days, all of whom asked for anonymity. Still, given the financial crisis and two wars, Obama is bound to move more quickly than either of his two predecessors in making key personnel decisions.

Summers, 53, is favored to return to the Treasury post that he held under President Bill Clinton because Obama values his experience and familiarity with markets and global leaders, a crucial asset during the markets crisis.

Still, people close to the president-elect stress no final decision has been reached and that Timothy Geithner, president of the New York Federal Reserve, is also a strong contender. Geithner would also be welcome by many in the financial community; at age 47, he would be a fresh face in an administration that ran on a mantra of change.

Obama's first decision may be who heads his White House operation. "A president should pick a White House chief of staff first," says Vernon Jordan, the lawyer and investment banker who ran the transition for Clinton in 1992. "The chief of staff needs to be involved in the selection of other people in the government; that's the quarterback."

Obama has spoken with Emanuel, the No. 4 ranking Democrat in the House of Representatives and former Clinton White House aide, in recent weeks about the post; if asked, Emanuel is expected to accept.

Emanuel would bring an exceptional understanding of the nexus between politics and policy and of the way Washington works, critical requisites for that job.

His detractors say his tough, take-no-prisoners approach is antithetical to the tone and style of the Obama presidential campaign.

Still, if, as many expect, top campaign strategist David Axelrod and businesswoman and Obama confidant Valerie Jarrett become counselors to the president, they would form a powerful Chicago troika running the White House.

On the national security front, the first decision may be whether to ask Defense Secretary Robert Gates to remain for an interim period, a move favored by a number of influential congressional Democrats and the military. As the new president focuses on the financial crisis, they argue, this would offer continuity.

"He's done an extraordinary job," Sen. Jack Reed, a Rhode Island Democrat, said of Gates. "I would hope that in some capacity he could continue to serve."

If Gates isn't asked to stay, a leading candidate for Defense would be retiring Republican Sen. Chuck Hagel of Nebraska. Hagel accompanied Obama on his trip to Afghanistan and Iraq in July, and the two have become close. The Illinois senator has said he wants a bipartisan Cabinet.