In a closely watched West Sacramento school board race, a union-backed teacher beat out a candidate endorsed by the mayor and bankrolled by groups challenging labor power.

The election was seen as a test case among education activists seeking to weaken teachers unions and install board members focused on overhauling education through charter schools and shaking up teacher hiring and firing practices.

Sarah Kirby-Gonzalez, who raised just under $30,000 mainly from unions, garnered 50.7 percent of votes for a seat on the tiny Washington Unified School District. The special election was called to fill the remaining 18 months of a seat on the board, which governs nine schools with just over 7,400 students.

Francisco Castillo, who was endorsed by West Sacramento Mayor Christopher Cabaldon, trailed with 25.9 percent of the votes.

Castillo's campaign raised a total of about $59,000, including a big boost of $35,000 from StudentsFirst, the group founded by former Washington, D.C., public schools chancellor Michelle Rhee that has taken on teachers unions. Castillo serves as the organization's deputy national press secretary.

Cabaldon threw his weight behind Castillo in a bid to change the direction of the board and improve performance in the diverse school system. The mayor saw the election as a defining moment of his 14-year tenure.

Kirby-Gonzalez said her solid victory emphasized that parents in the school district didn't want big money and outside influences to dictate classroom policy.

"People saw StudentsFirst as firing those teachers and changing things around, and I don't think that's what parents want," she said Tuesday night. "I'm not for the status quo. I'm for change. All teachers are for change, but from people who really understand education, instead of people from the outside or billionaires pouring money in to our campaigns."

Castillo said the special election, which was all-mail for the first time in the county, had low voter turnout and may have been confusing for some voters. He plans to run for one of two open school board seats in November 2014.

Cabaldon said he was disappointed in the election results, but acknowledged the margin reflected a strong voice from voters.

"I believe we need to accelerate the improvements in our schools, but the evolution of the board is showing marked improvement in the strength of the board, and I remain hopeful of the overall trajectory of the board," Cabaldon said.

Linh Nguyen came in third place with 14.5 percent. Katherine R. Gales received 5 percent, while Nicholas Scott Turney got 3.9 percent.

Rhee's StudentsFirst also supported candidates in Tuesday school board elections in Los Angeles and Burbank.

In Los Angeles, the group was joined by New York City Mayor Michael Bloomberg in promoting a slate of change-minded candidates. Bloomberg gave $1 million to a coalition formed by Los Angeles Mayor Antonio Villaraigosa to elect candidates who support policy changes in the district.

Rhee's group called the campaign contributions a testing ground for reshaping boards and making aggressive changes.

Call The Bee's Anne Gonzales, (916) 321-1049.

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