SAN FRANCISCO (CBS / AP) — Incumbent Tom Torlakson maintained an early lead Tuesday in what had been expected to be a tight race for the job of California’s K-12 schools chief, a nonpartisan and largely ministerial post that in the months leading up to Election Day became an expensive battle ground with high stakes for teachers unions and education reformers.

With 15 percent of precincts reporting, preliminary returns showed Torlakson in front with 54 percent to challenger Marshall Tuck’s 46 percent.

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The contest between the two Democrats has been one of the most hotly contested in California this year. Spending in the race exceeded $22 million, making it the most expensive election for a statewide office apart from the governor’s race.

“We are pretty excited about what we see so far, but we have to take a look and see. If the early returns look like the late returns, we will certainly have a very happy night,” said Torlakson campaign manager Paul Hefner, who was awaiting the election results along with the candidate at a party in Sacramento hosted by the California Teachers Association.

Torlakson, 65, is a former high school science teacher and state lawmaker who was elected superintendent of public instruction four years ago. He has the backing of the unions, the California Democratic Party and the majority of county school superintendents.

Tuck is a former charter schools executive and first-time candidate who built his candidacy around his support for a June court ruling that overturned the state’s generous tenure laws and other job protections for teachers, a position that distinguished him from his opponent. He secured endorsements from all of the state’s major newspapers.

Tuck’s upstart campaign also benefited from at least $10.7 million in independent expenditures by the widow of Apple founder Steve Jobs, former New York Mayor Michael Bloomberg and other business and technology leaders.

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Speaking from an election night party at the candidate’s home, campaign manager Cynara Lilly said she was “cautiously optimistic” based on the first rounds of returns.

“What the numbers do show is there is an incredible demand for change in California,” Lilly said. “This campaign was an incredible coalition of Democrats, Republicans, independents, parents, teachers, families. This is a real movement for change in California. And no matter what, we are incredibly proud of the work we have done and will continue to do to improve California schools.”

The election’s outcome was being watched outside California as a referendum on the direction of the state’s underachieving education system and on the powerful role organized labor, especially education unions, has played in the Democratic Party both nationally and in Sacramento.

Torlakson has argued that the state needs steady and experienced leadership as schools rebound from deep budget cuts during the recession and begin to implement curriculum and testing changes associated with new standards.

Tuck, who supports tying students’ standardized test scores to teacher evaluations and merit pay, accused Torlakson of being tied to a failed status quo that prioritized the wishes of the unions over the needs of California’s 6 million public school students.

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