Richmond is set to become the largest city in America with a Green Party mayor, after the election Tuesday of Gayle McLaughlin, and party leaders say her victory thrusts a group once defined as middle-class environmentalists into a new role as a multicultural force in local politics.

In the past decade, Green Party members have served as mayors in nearly two dozen predominantly white cities in California, from Sebastopol to Santa Cruz and Davis.

But the strong showing of McLaughlin in the gritty, cash-strapped East Bay city, where about three-fourths of the 103,000 residents are minorities, would mark an enormous shift in the political demographic of Green Party support.

"The defining thing is that this is a direct election in a major urban center, so it is definitely our biggest win," said Susan King, the Green Party's California spokeswoman. "The victory signals for us that we are moving beyond our base, that we can have an impact in minority communities and actually have some pull with working-class people."

With most ballots counted, McLaughlin, a 54-year-old city councilwoman, leads Mayor Irma Anderson by 192 votes in a three-way race for mayor. McLaughlin received 37.2 percent of the votes, followed by Anderson with 36.1 and businessman Gary Bell with 26.1. The rest of the tallied votes were for write-in candidates.

Anderson refused to concede defeat Wednesday, saying she would wait until all the provisional and late absentee ballots are counted, which will take at least a week. But few people believe she can make up the deficit.

McLaughlin, who was elected to the council four years ago, said being an environmentalist allowed her to understand the troubles in Richmond's neighborhoods, including high rates of childhood asthma in areas near refineries and heavy industry.

"I stand for a sustainable environment," said McLaughlin, who helped found a local group called Solar Richmond. "We have too much pollution in Richmond. We need to clean many toxic sites left by many years of manufacturing."

McLaughlin, a former schoolteacher, said her campaign was all about promoting the "people's interests over corporate interests." To combat the city's high crime, she said she will launch a job corps for local youth so young people can help with street repair and park maintenance.

"I want to put 1,000 kids to work throughout my term," McLaughlin said. "We should be dealing with our existing neighborhoods and our existing quality of life. That will bring in businesses."

Jack Citrin, a political science professor at UC Berkeley, attributed the election results more to dissatisfaction with Richmond's current mayor than any ideological shift in the city toward Green Party politics.

Such dissatisfaction motivated Terrell Temple, whose parents, grandparents and an aunt live near John F. Kennedy Park in central Richmond, where a man was shot to death recently while sitting in a car parked across the street from one of the "tent cities" erected in a stand against violence.

"I have an aunt that lives on the other side of the park, and she got held up at gunpoint going from her car to her house (late last year)," said Temple, 41, who grew up in Richmond and now lives in Fairfield. "I'm for any change that will help out in this city -- anything that will help stop the violence is a plus."

Bruce Cain, another UC Berkeley political science professor, said the key question is whether McLaughlin can solve the nuts-and-bolts issues of municipal leadership.

"In the end, whether you are progressive or conservative, you have to provide the everyday services that people expect out of city government -- the lights, the water, the police, the fire, the emergency services," Cain said. "What the new mayor does in Richmond will help develop an image people have about what the Green Party is and whether it can govern."

Larry Robinson, a green mayor in Sebastopol in 2001 and 2005, said the Green Party focuses on creating sustainable communities.

"The issues that we are concerned about in our white, middle-class communities are the things that working-class and minority communities are concerned about -- economic and environmental justice, affordable housing, a living wage, good schools for our kids and health care," Robinson said.

McLaughlin is set to become California's first elected Green Party mayor. All 22 previous green mayors in the state, including mayors in Fairfax, Sonoma, Sebastopol, Davis, Arcata and Santa Cruz, were appointed as part of a mayoral rotation.

In all, 31 U.S. cities have had green mayors, beginning in 1991 with Kelly Weaverling's election in Cordova, Alaska, amid widespread anger over the Exxon Valdez oil spill.

Larry Barnett, a two-time Green Party mayor in Sonoma, said McLaughlin's victory in Richmond shows that communities are more interested in solutions than they are in partisan politics.

"I think people are simply looking for authentic candidates and officeholders who have values that the voters can identify with," Barnett said. "As a Green Party candidate, you are not tied down to an affiliation with either political party."