(AP) - President-elect Barack Obama picked former campaign rival Hillary Rodham Clinton as secretary of state Monday. He also announced that Robert Gates would remain as defense secretary, making President Bush's Pentagon chief his own as he seeks to wind down the U.S. role in Iraq.

Clinton's nomination as secretary of state is another milestone for a former first lady whowas the first to win elective office, the first to run for president herself and now the first to be chosen for a Cabinet position.

Although she lost her White House bid this year, Clinton is continuing a climb through the ranks of public service that began even before her marriage to Bill Clinton, who would become president.

She came to Washington after graduating from Yale Law School to advise the House Judiciary Committee on the impeachment proceedings against President Richard Nixon. She earned a reputation for hard work and mastery of her research topic, but left the capital for Arkansas, where her boyfriend was running for office.

She would follow him from the Arkansas governor's office to the White House, where she was more than an average first lady handling ceremonial roles. She spearheaded the Clinton health care plan, which failed to gain congressional approval and helped Republicans win control of the Senate and House in 1994.

As her husband left office, Clinton ran for an open seat representing New York in the U.S. Senate, marking the first time a first lady ever ran for elective office. Even though she had moved only recently to the state, Clinton won with 55 percent of the vote, and she earned a reputation for reaching across the aisle to build alliances in both parties.

She entered the 2008 Democratic presidential primary as the clear front-runner, but Obama overtook her. The two fought amarathon race that didn't end until every state held a primary orcaucus, with Clinton doggedly persisting even when Obama built asignificant delegate lead and her chances for victory wereminuscule.

Clinton backed Obama in the general election, endorsing him insymbolic Unity, N.H., and traveling across the country in supportof his candidacy. A week after Obama won, he secretly met withClinton in Chicago to discuss the secretary of state job. Sheagreed to take it with the support of her husband, who agreed totake several steps to avoid conflicts of interest, includingdisclosure of donors to his library and international foundation.

Watch Chappaqua residents' reaction to Clinton's nomination Watch Sen. Clinton's comments