FACTBOX: Obama's Cabinet begins to take shape

(Reuters) - President-elect Barack Obama has nominated Timothy Geithner as his Treasury secretary and Lawrence Summers to head the National Economic Council, filling two of the most closely watched jobs in his administration.

A senior Democratic source said on Tuesday Obama also intended to ask Secretary of Defense Robert Gates to remain on the job.

Here are people Obama has chosen or is considering for key posts. Many remain subject to vetting and Senate confirmation before taking office.

SECRETARY OF DEFENSE

* Current Defense Secretary Robert Gates, named by President George W. Bush in late 2006, is considered a moderate voice on the Republican's national security team and could embody an important signal of continuity.

A senior Democratic source told Reuters Obama intended to ask him to stay on and that he was likely to accept.

Gates, a former CIA director, took over the U.S. Department of Defense from the combative Donald Rumsfeld and has run things with a low-key approach that seeks to build constructive relationships but also betrays a steely firmness of purpose in the two U.S. wars in Iraq and Afghanistan.

NATIONAL SECURITY ADVISER

* Retired Marine Gen. James Jones, the former top operational commander of NATO, is a leading contender for White House national security adviser and the Politico news website said on Tuesday the deal had been done.

Jones is widely respected by both Democrats and Republicans but has avoided aligning himself with either party.

He is known to have been a strong critic of the Bush administration's handling of the Iraq war and is quoted as describing the war as a "debacle," in Washington Post journalist Bob Woodward's 2006 book "State of Denial."

TREASURY SECRETARY

* Timothy Geithner, president of the New York Federal Reserve Bank, is Obama's choice for the Treasury Department, making him Obama's point person in dealing with the economic crisis.

Geithner has helped lead efforts to stabilize financial markets and argued that banks crucial to the global financial system should operate under a unified regulatory framework.

Geithner's appointment was made official on Monday by Obama, who said he would bring "an unparalleled understanding of our current economic crisis" to the job.

NATIONAL ECONOMIC COUNCIL