Mayor Tom Bradley won a third term with a landslide victory likely to catapult him into the 1982 governor's race.

Bradley won about 64 percent of the vote Tuesday against his longtime political nemesis, former mayor San Yorty, who got about 31 percent.

The election, the first time a Los Angeles mayor has won a third term without a runoff, was a tribute to Bradley's popularity among blacks, Hispanics and other minorities who no form a majority of the city's population, but it also demonstrated his support among businessmen who like his revitalization of downtown.

A recent statewide Field poll gives Bradley the highest favorable rating of any politician in the state, leading many to suggest that he could become the first elected black governor in U.S. history. Asked about his plans to run for governor, Bradley said, "Let me savor this for a few days."

Bradley would be expected to beat the most frequently mentioned challenger in the Democratic gubernatorial primary, former U.S. senator John V. Tunney, but would have a much more difficult time against the likely Republican candidates, Lt. Gov. Mike Curb, Attorney General George Duekmejian, and San Diego Mayor Pete Wilson.

Edmund G. (Jerry) Brown Jr., the Democratic governor, is expected to run for the Senate in 1982.

In other voting Tuesday, two strong opponents of court-ordered busing to integrate public schools were reelected to the school board. Board President Roberta Weintraub and board member Tom Bartman, a leading legal adviser to the parents' group that successfully challenged the busing plan, both won more than 150 percent of the vote in their districts, and thus avoided runoffs.

Alan Gershman, a former busing supporter who later turned against busing as "poor public policy," led in a third school board race, but face a runoff.