Governor Mark Warner has made it official.

He announced on a radio call-in show that he won't run for the U.S. Senate next year. Warner told WTOP in Washington that he'll work to recruit a strong Democrat to challenge Republican Senator George Allen.

Warner said he's making his intentions known now so he won't be distracted as he winds up his term as governor. The Democrat said he still has much to do before he leaves office in early 2006.

Warner said he has not ruled out another bid for governor in 2009. Governors cannot serve two consecutive terms under Virginia law.

Governor Warner has been making numerous national appearances in recent months, and has been mentioned by pundits as a viable presidential contender.

As he explores his options, the governor formed a federal campaign committee this summer and hired Monica Dixon, a top political adviser to Al Gore's 2000 presidential campaign.

Warner had a job-approval rating of 74 percent in a statewide survey conducted last month by Mason-Dixon Polling & Research Inc. It was the highest mark for any Virginia governor in the final months of his term in the 20 years the firm has been conducting the poll.

For months, Allen has used the prospect of a Warner challenge to stimulate his fundraising appeals to Republicans determined to keep the seat in GOP hands.

The Democrats have made it clear that they are going to send someone up against us, and Senator Allen will be prepared for a battle," Allen political aide Jason Miller said Monday.