Catalina Camia

USA TODAY

GOP Rep. Buck McKeon of California, chairman of the House Armed Services Committee and an ally of Speaker John Boehner, made it official Thursday and said he won't run for a 12th term.

McKeon, 75, is slated to give up Armed Services gavel at the end of the 113th Congress, as required by Republican term-limit rules for committee chairs. He's led the powerful panel overseeing Defense Department programs since 2011.

"After you've been chairman of the committee, then what do you do?" McKeon told the Los Angeles Times in an interview.

McKeon was first elected in 1992 to represent a district in northern Los Angeles County. Mitt Romney carried California's 25th District in the last presidential election, the first since its boundary lines were redrawn, but Barack Obama won there in 2008. House Democrats vowed to mount a competitive race to take the seat.

Boehner, who worked with McKeon on the House Education and Workforce Committee, saluted his "close friend and confidant" of more than 20 years as a "tireless advocate" for the military, defense civilians and their families.

As head of the Armed Services Committee, McKeon resisted cutbacks at the Pentagon and the automatic, across-the-board spending cuts known as sequestration. He voted against repealing the "don't ask, don't tell" policy that banned gays and lesbians in the military, arguing it would hurt military readiness.

McKeon is the 10th Republican to announce his retirement from the House, according to a list compiled by Roll Call.

His retirement has been expected. Two California Republicans -- former state senator Tony Strickland and current state Sen. Steve Knight -- have already formed campaign committees in anticipation of McKeon stepping aside in January 2015.

McKeon was also signaling that he wants Rep. Mac Thornberry, R-Texas, to take over the Armed Services Committee chairmanship when he retires.

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