HOUSTON - Annise Parker has an unbeatable lead over Gene Locke in Houston's hotly contested mayoral election, meaning she will become the city's first openly gay mayor.

The Harris County elections Web site says 53.62 percent of voters who turned out yesterday chose Parker.

Her rival, former city attorney Gene Locke, was pitching to become the city's second black mayor.

The election battle was marked by fierce campaigning and antigay rhetoric. Parker is a lesbian who has never made a secret or an issue of her sexual orientation. Houston will become the largest U.S. city to have an openly gay mayor.

Parker's sexual orientation became the focus of the race in recent weeks after antigay activists and conservative religious groups endorsed Locke, 61, and sent out mailers condemning Parker's "homosexual behavior." Meanwhile, gay and lesbian political organizations nationwide rallied to support Parker, 53.

A poll released by Rice University last week showed Parker leading Locke 49 percent to 36 percent. The poll, commissioned by television station KHOU and radio station KUHF, was based on telephone interviews with 442 registered voters in Houston. It has an error margin of 4.7 percentage points.

Parker and Locke, both Democrats in the nonpartisan race, made it to the runoff after garnering more votes than two other candidates on Nov. 3. They were vying to replace Bill White, who is term-limited after serving six years.