With a record $24 million spent on the election so far, are special interests trying to buy their way into the Legislature?

Cecilia Aguiar-Curry, a Democratic Assembly candidate from the small Northern California farming town of Winters, got a surprise when she bumped into a friend at a local coffee shop.

“A friend said, ‘Oh, I saw your commercial,’ ” recalled Aguiar-Curry, the town’s mayor. “I said, ‘You’re mistaken. I don’t have a commercial.’ ”

That was technically true — it wasn’t her commercial, even though it was aired to support her campaign. Like many advertisements flooding airwaves and mailboxes this year, it was paid for directly by powerful interest groups seeking the upper hand in the California Legislature.

Independent expenditures already have cracked $24 million in the run-up to the June 7 primary, with millions more likely to come in over the next week. The spending has set a record and is a hefty increase from $16.7 million spent two years ago.

The result? Voters are hearing less from the candidates they’re electing and more from oil companies, education advocates, business groups and labor unions.

“The candidate is not controlling the message,” said Bob Stern, an attorney who helped write California’s campaign finance rules. “It’s special interests trying to control the race and buy their way into the Legislature.”

One of the most lopsided examples of the role played by independent expenditures this year can be found in Aguiar-Curry’s campaign. She’s raised only $164,000 in direct contributions for her primary run, but outside groups have spent more than $1.7 million to support her.

It’s a situation Aguiar-Curry described as “awkward” — some of the money is coming from oil and tobacco companies, organizations whose cash she said she doesn’t want in her personal campaign account.

“I would like to have control over what is said about me,” said Aguiar-Curry, a businesswoman whose family owns a walnut farm. “I can’t do anything, and so it’s really put me on my heels a bit.”

One of her four opponents, Davis Mayor Dan Wolk, a Democrat, has received $38,000 in assistance from teachers and consumer attorneys.

State law prevents candidates from coordinating with independent groups, which can spend unlimited amounts while contributions to legislative candidates are capped at $4,200 per donor. Although sources of the money to the independent groups are publicly disclosed, the donations often are funneled through political action committees, California’s equivalent of the “super PACs” that have become increasingly influential in federal elections.

In one Assembly race in San Bernardino County, the biggest players are the Coalition to Restore California’s Middle Class, a committee financed by oil companies that are supporting Assemblywoman Cheryl Brown, and Neighbors United for a Stronger Middle Class, which is funded by unions backing Brown’s challenger, attorney Eloise Gomez Reyes.

The battle between the two Democrats has attracted some of the highest levels of independent money in the state: roughly $2 million at last count. By comparison, the candidates themselves have raised less than $1 million.

It’s a reflection of how California’s new primary system, approved by voters in 2010, has increased the significance of rivalries among Democrats. The top two finishers in the primary advance to the general election, regardless of their party. Given the unmistakable dominance of Democrats in state politics, business groups that once backed Republicans are now switching sides in hopes they will continue to wield influence in the Capitol.

“The various interest groups have learned, especially on the business side, that they can have an impact with the top two and open primary that they could not have when we still had a closed primary,” said Tony Quinn, a veteran Republican election analyst.

There are also higher stakes in legislative elections because of the 2012 change in term limits. Once a lawmaker reaches Sacramento, he or she can serve up to 12 consecutive years in the Assembly or the Senate.

Another driving factor in the race between Brown and Reyes is the battle over climate change legislation. Brown is one of the Democrats who opposed a state measure to cut oil consumption for transportation in half by 2030.

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The union-backed group opposing Brown has pegged her as “Chevron Cheryl,” accusing her of allowing “dirty air” by taking “dirty money.” The group supporting Brown, meanwhile, thanks her in its campaign videos for standing up to “fancy-pants politicians” who it said wanted to limit the amount of gasoline available.

Asked whether she is being pegged as an “oil candidate,” Brown said, “I don’t see where it’s such a horrible thing. In our area, people want to be able to go to work, and they want to have clean air.

“But we have no mass transportation in the Inland Empire,” she added. “And the buses do not go where the jobs are.”

Chevron has put $2 million into the independent group backing Brown and other candidates, in addition to $2 million from Valero, $1 million from Tesoro and $500,000 from the California Resources Corp. In a statement, Chevron said it wants to help “advocate positions designed to support free markets and fair energy industry legislation and regulations.”

A similar battle is playing out in the Bay Area among two San Jose Democrats. Sen. Jim Beall, aided by billionaire environmental activist Tom Steyer, is defending his seat against a challenge from Assemblywoman Nora Campos, who is backed by oil companies.

“If we want our leaders to stand up to powerful interests and do right by our families, we can’t allow Big Oil to bully them into silence,” Steyer said in a statement. He’s pledged to put $500,000 behind Beall.

Chevron, Tesoro and Valero have put $340,000 into efforts to support Campos, who criticized Beall and Steyer as “out of touch and clueless to the plight of the working-class men and women of our region.”

Another heavy spender in this year’s primaries is EdVoice, which has put more than $4 million into six races. The organization has been supported by several wealthy donors, including Arthur Rock, a Silicon Valley investor who has contributed $1 million. Bill Bloomfield, a Los Angeles-area businessman, gave an additional $1.4 million this year.

Bill Lucia, president of EdVoice, said the group is looking to help candidates who will “come and be champions for kids in Sacramento” rather than look at “public education as a full employment program for adults.”

The Legislature has been split by disagreements on school policies, particularly over how important student test scores should be when evaluating teachers, or whether to weaken tenure rules to make teachers easier to replace.

One of EdVoice’s favored candidates is Tim Grayson, a Concord City Council member running for an Assembly seat in the Bay Area.

“They’re perceiving me as someone who is definitely serious about dealing with the real issues of education,” Grayson said.

Grayson’s opponent is Mae Torlakson, a member of a local park district board and the wife of Tom Torlakson, the state superintendent of public instruction. Education groups unsuccessfully tried to prevent his reelection to the state’s highest education post in 2014, and now they’re trying to block his wife’s ascent to the Assembly.

“I know they do not represent the people, and most of them are not from the district,” Mae Torlakson said. “They see me as a threat for some reason.”

Torlakson, of course, has her own powerful supporters. A union-backed group paid for polling and mailers, and the California Teachers Assn. spent $100,000 to produce and air television advertising.

She said their support is different because it comes from groups representing middle-class workers.

“This will be a people-powered campaign,” she said.

Times staff writer Christine Mai-Duc contributed to this report.

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chris.megerian@latimes.com

Twitter: @chrismegerian