The top 10 donors to November's state ballot measures – a smattering of extremely wealthy people, powerful unions and large corporations – have dumped more than $150 million into the fight so far, according to campaign finance tracker MapLight.org.
The mega-donors include politically opposed siblings, a 91-year-old car insurance magnate, a conservative group that keeps its donors secret and a teachers union that has outspent every other special interest in the last decade. MapLight.org tracks the top donors of each ballot initiative on its Voter's Edge website.
At the top of the list this year is civil rights attorney Molly Munger, who has given nearly $30 million of her own fortune to pass Proposition 38 [PDF], which would raise taxes to fund K-12 education. Her father is a billionaire business partner of Warren Buffett at Berkshire Hathaway.
"Molly Munger is investing her own money in the campaign because she cares deeply about the state of public education," Nathan Ballard, campaign strategist, said in an email.
The California Teachers Association, for example, gave nearly $8 million to Brown's measure, according to MapLight. The union is one of the heaviest hitters in California politics. From 2001 to 2011, it gave more than $118 million to candidates and initiatives, more than any other interest group, according to a previous California Watch analysis.
This season, the union also has forked more than $18 million to try to defeat Proposition 32 [PDF], which would weaken the clout of unions by barring the use of payroll-deducted dues for political purposes.
The Service Employees International Union unloaded more than $20 million, also to support Prop. 30's tax increase and oppose Prop. 32. The California Federation of Teachers added nearly $3 million to those efforts.
On the other side of those initiatives, Munger's half-brother, Charles Munger Jr., has spent $23 million to pass the proposition on union dues and oppose the governor's tax measure.
Munger Jr., a Stanford University physicist and Republican activist, has been a top donor for years. In 2010, he successfully proposed and funded an initiative that gave the task of redrawing congressional districts to an independent commission.
An Iowa advocacy group called the American Future Fund gave $4 million to support Prop. 32, the measure that would affect unions. The conservative group doesn't disclose its donors but reportedly has ties to the billionaire brothers Charles and David Koch.
Further down the ballot, hedge fund manager Thomas Steyer is bankrolling Proposition 39 [PDF], which would change the way multi-state companies are taxed to raise money for alternative energy projects and the state general fund. So far, Steyer has given $22 million to the effort.
"This isn't Tom Steyer alone working on a pet project," said campaign spokeswoman Alexa Bluth. "This is Tom Steyer using his resources to help with a ballot initiative that will be good for all of California."
Steyer, a partner at a private equity firm, also spent millions to help defeat a 2010 initiative that would have weakened California's global warming legislation.
The billionaire chairman of Mercury Insurance is funding an initiative of his own. George Joseph dropped more than $16 million into Proposition 33 [PDF], which would let car insurance companies base rates on whether a customer previously had been insured.
Joseph has been fighting for the change for years. His company spent $15.8 million on a similar 2010 initiative, but it failed at the ballot box. Opponents have criticized Joseph for trying to benefit his own company.
"I really think he wants to leave this as his legacy," said Prop. 33 spokeswoman Rachel Hooper. "He really believes that the insurance industry can be more competitive and robust."
This year stands out for the number of mega-donors and the huge gush of funding, said Kim Alexander, president of the California Voter Foundation.
"The amount of money is at levels that I haven't seen among individual donors," she said.
Deep pockets are necessary to pay signature gatherers and qualify an initiative for the ballot, but money isn't everything, Alexander said.
"You can’t win an initiative campaign without money, but you can’t win with only money, either," she said. "I have yet to see anyone buy an initiative."
Most initiatives fail. And it's easier to kill an initiative with big money than to pass one, she said.
Alexander also points to a few measures that made it to the ballot with less money. Proposition 34 [PDF] would repeal the death penalty; Proposition 36 [PDF] would alter the state's three strikes law; and Proposition 37 [PDF] would require labeling of genetically engineered foods. All raised millions, but nowhere near the amounts that the tax measures have garnered.
"None of those have a ton of money, and none of those would go anywhere in the Legislature," Alexander said. "And that’s why you have the initiative process."
The food labeling measure does have deep-pocketed opponents. Monsanto and DuPont, companies that make genetically modified seeds, have spent $7 million and $5 million, respectively, to defeat Prop. 37. Both could be affected if food companies switch to non-genetically modified ingredients, as critics of the measure fear.
In a report [PDF] this week, the Public Policy Institute of California called for more transparency in the initiative process.
"Voters are often uncertain about the identity and motives of initiative proponents and opponents," it said.
Those interests should be disclosed on official voter pamphlets and actual ballots, the report recommended. Legislation that would have listed top donors on voter pamphlets was vetoed by Brown last year.
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This story was produced by California Watch, a part of the nonprofit Center for Investigative Reporting. Learn more at www.californiawatch.org.