In the battle for the future of California's schools, charter school advocates are far outpacing teachers unions in spending to support candidates for governor and state schools chief.
Wealthy donors who support charter schools and education reform have poured more than $22 million into independent committees to support former Los Angeles mayor Antonio Villaraigosa for governor and former schools executive Marshall Tuck for state schools chief. Many of the same donors have also contributed directly to Villaraigosa's and Tuck's campaigns.
The independent committees aren't subject to campaign contribution limits but are prohibited from coordinating messaging with the candidates.
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Teachers unions have dropped about $4 million on independent committees to back Lt. Gov. Gavin Newsom for governor and Assemblyman Tony Thurmond for superintendent. Teachers unions and other organized labor groups have also contributed to Newsom's and Thurmond's campaigns.
All four men are Democrats who want more education funding. But they differ on state officials' role in improving schools and how to handle nonprofit charter schools, which are publicly funded but typically run independently of the traditional public school system.
Studies on how effective charter schools are compared with traditional public schools have mixed results. California has about 1,200 charter schools, but the vast majority of its students attend non-charter schools.
Currently, most California students score below grade-level standards in math and English on standardized tests, according to data from the state Education Department.
The state superintendent of public instruction and governor have power to shape California education policy -- the superintendent as head of the education agency and board of education, and the governor as a key player in state budget decisions and the final word on legislation.
Netflix founder Reed Hastings and former New York Mayor Michael Bloomberg are two of the major donors behind a $17 million independent effort to support Villaraigosa ahead of the June 5 primary, where he needs to finish first or second to advance to the general election. Newsom is widely considered the front-runner, with Villaraigosa battling for second against Republicans John Cox and Travis Allen and Democrats Delaine Eastin and John Chiang.
Villaraigosa said he refused to promise teachers unions he would limit the number of charter schools, and instead said he would put a moratorium on failing schools, whether charter or traditional. "What I've told them is when their interests meet the public interest, I'm all in," he said.
As mayor, Villaraigosa worked with Tuck, who led the nonprofit Partnership for Los Angeles Schools, to take over several failing L.A. schools and improve their graduation rates.
Villaraigosa's strained relationship with the unions dates to that time, said Joshua Pechthalt, who was a teacher in Los Angeles for over 20 years. At one point, Villaraigosa was his union representative, said Pechthalt, who now leads the California Federation of Teachers, which endorsed Newsom.
"Initially we supported him for mayor, but that began to change as his approach began to change," Pechthalt said. "Rather than seeing educators as collaborators, he was going to dictate what was going to happen."
Teachers unions criticize Villaraigosa for the millions he's receiving, arguing education reform should start with teachers, not wealthy donors.
Charter advocates say they support more dramatic school-system changes than the unions support.
"Because they have more flexibility, they're able to be, many times, more innovative and creative," Tuck said. He supports more choice for families, including nonprofit charter schools. He's backed by an independent committee with over $5.7 million, mostly from prominent charter school supporters.
Arthur Rock, a San Francisco Bay Area businessman who has given millions to groups supporting Tuck and Villaraigosa, says he believes they are committed to education reform. In an email, he called the low education outcomes for underprivileged kids in San Francisco a "tragedy."
A Bloomberg spokesperson said he supports Villaraigosa and Tuck because their past work shows they would improve schools.
Teachers unions say they want more oversight for charter schools. One of the largest, the California Teachers Association, donated more than $1 million in an independent expenditure account supporting Newsom.
"He believes in attracting teachers, not attacking teachers like we've seen from other candidates," union spokeswoman Claudia Briggs said.
Newsom says he supports high-performing charter schools but believes they need to operate more transparently. He criticized Villaraigosa's support for expanding the number of charter schools in Los Angeles.
"He's indulged them," Newsom said of the wealthy charter-school supporters. "He's being rewarded in the most crass sense of the term rewarded."
Teachers unions have also endorsed Thurmond and have spent more than $2.7 million to support him.
Thurmond said he doesn't oppose charter schools, but he doesn't want them to siphon money from existing public schools.
"The focus should be on serving the schools that we have," he said.
He and Newsom have been criticized for being too closely aligned with unions, which they dispute.
The schools chief race is nonpartisan. If any candidate wins more than half the vote in June, they win the race outright. Otherwise, the top two candidates advance to the general election. There are four candidates in the race, but only Thurmond and Tuck have reported financial backing.
Tuck ran for the seat unsuccessfully in 2014. Incumbent Tom Torlakson beat him with backing from unions.