After keeping Democrats on the edge of their seats for days, former U.N. Ambassador Andrew Young (search) announced Friday that he will not run for the U.S. Senate.

That leaves the post being vacated next year by retiring Sen. Zell Miller (search) without a significant Democratic challenger.

"I decided that I could not be the candidate," he said. "I was afraid I'd win. Winning would mean I would spend the next seven years of my life in Washington, and Washington is not always the center of action."

Friday's decision follows a breakfast meeting Thursday during which Young told Democratic Study Group on National Security (search) he was "in the process" of preparing a campaign.

However, Young acknowledged he expressed concerns about the race in a recent meeting with family and friends that he thought was private, but he said those comments shouldn't be interpreted to mean he's not running. He said he is on the "same course" as he has been the last several months, during which most Georgia Democrats have rallied around him as their leading candidate.

No prominent Democrats have announced for Miller's seat, while four Republicans, including congressmen Mac Collins and Johnny Isakson, are already campaigning. The only announced Democrat is little-known state Sen. Mary Squires of suburban Atlanta.

Young, 71, was a congressman, U.S. ambassador to the United Nations, Atlanta's mayor for two terms and a gubernatorial candidate in 1990, losing to Miller in a primary runoff.

Young's rise to prominence began in the civil rights struggle, when he was a top lieutenant of the Rev. Martin Luther King Jr (search). His election to the U.S. House in 1972 made him the first black elected to Congress from Georgia since Reconstruction (search).

President Carter named him U.N. ambassador. Young resigned the post in 1979 amid a public uproar over a clandestine meeting he had with members of the Palestine Liberation Organization (search).

Two other potential candidates - Michelle Nunn (search), the 36-year-old daughter of former Sen. Sam Nunn, and U.S. Rep. Jim Marshall (search), a freshman Democrat from Macon, have said they would not run if Young enters the race. Marshall was the only one of Georgia's five House Democrats who didn't attend the breakfast.