In this file photo, Democratic presidential hopeful Sen. Barack Obama D-Ill., left, and New Mexico... 
(Alex Brandon/AP Photo)His appointment adds more demographic diversity to a Cabinet that already includes several women and blacks. Richardson is the first Hispanic named to Obama's Cabinet.
Obama is considering another Hispanic politician, California Democratic Rep. Xavier Becerra, to be U.S. Trade Representative, according to two Democratic officials speaking on a condition of anonymity ahead of an announcement for the position.
New Mexico's Lt. Gov. Diane Denish, a Democrat, will become the state's first female governor when Richardson leaves to assume his new post. Denish will take over for the remainder of Richardson's term, which runs through 2010.
In neighboring Arizona, Obama's selection of Democratic Gov. Janet Napolitano to serve as secretary of Homeland Security will put the state in the hands of a Republican governor.
Under Arizona law, Secretary of State Jan Brewer, a Republican, will take over from Napolitano.
The president-elect is moving quickly to fill his Cabinet, having identified choices for more than half the positions since he was elected the country's 44th president.
As a former energy secretary and U.N. ambassador, Richardson had been a contender for the job of Secretary of State, which ultimately went to Clinton.
Among those Cabinet posts yet to be disclosed if not chosen: the heads of the Interior, Transportation, Labor, Energy, Housing and Urban Development, Education, Agriculture and Veterans Affairs departments. Obama also has yet to name his intelligence team, including his director of national intelligence and CIA chief.
Lisa Jackson, the former commissioner of the New Jersey Department of Environmental Protection, has emerged as the front-runner to head up the Environmental Protection Agency, according to two Democrats familiar with the transition who requested anonymity because the deliberations are supposed to be private.
Jackson is a chemical engineer who currently co-leads Obama's EPA transition team. Before joining state government in 2002, she spent 16 years at the EPA in Washington and New York.
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