This story comes courtesy of California Watch.

By Will Evans

The companies that make those candy bars leftover from Halloween don't want Californians to be spooked by scary tales of "Frankenfoods."

The Hershey Co., Nestlé USA and Mars Inc. - makers of such trick-or-treat favorites as Butterfinger, Kit Kat and Snickers bars - gave a combined $367,000 last month to oppose Proposition 37, which would require labeling of genetically modified foods. They are just a few of the major food and biotechnology companies that have poured more than $44 million into the fight against Prop. 37, according to campaign finance tracker MapLight.org.

Proponents of the measure, who have raised $7.3 million from donors - including a controversial alternative health website and organic food companies - argue that consumers have a right to know what's in their food and point out that some countries already require such labels. Opponents of the measure, with six times more money, are funding an ad blitz arguing that the measure is too complex, could raise food prices and will hurt farmers.

Foods made with genetically modified ingredients are extremely prevalent [PDF] in the grocery aisle. Seed companies use genetic engineering to make plants more resistant to pests and pesticides, and most corn in the United States is grown from such seeds.

The American Association for the Advancement of Science, which publishes the journal Science, says the technology is perfectly safe [PDF] and opposes labeling. Label supporters, including Consumers Union, which publishes Consumer Reports, say more safety studies must be done.

Monsanto, a major manufacturer of genetically engineered seeds and the popular Roundup weed killer, is the top donor to the anti-Prop. 37 effort, with $8.1 million. Chemical company DuPont gave $5.4 million, according to MapLight. Last month, the campaign took in contributions from food giants like Kraft and PepsiCo, as well as Syngenta, which makes seeds and pesticides. Each has contributed about $2 million so far.

"They've been carpet-bombing the state with a million dollars a day in deceptive ads," said Stacy Malkan, spokeswoman for the Prop. 37 campaign. "We haven't been able to counter this stuff because they're on the air every hour, sometimes four times an hour, on every station across the state."

The opposition campaign says it's not just big corporate conglomerates trying to kill the initiative. Farmers fear costly regulations, and grocery retailers large and small worry they'll be the target of frivolous lawsuits, said Kathy Fairbanks, spokeswoman for No on 37.

"There's no question that this measure makes it easy for lawyers to file baseless shakedown lawsuits," she said. "It creates a very rich, lucrative target for them."

The top donor supporting Prop. 37, with $1.1 million, is Illinois-based Mercola.com, which sells nutritional supplements and skin products marketed with videos of Dr. Joseph Mercola dispensing sometimes controversial health advice. Mercola has drawn warning letters from the Food and Drug Administration for unsubstantiated health claims and believes child vaccinations are tied to autism, a position refuted by the mainstream medical community.

On his website, Mercola writes: "The existing medical establishment is responsible for killing and permanently injuring millions of Americans."

"He's made a lot of strange health claims," Fairbanks said. "Do we want him dictating policy in California?"

Malkan said the Prop. 37 campaign doesn't endorse Mercola's stances. She counters that Henry Miller, the expert appearing in No on 37 campaign ads, advocates the use of DDT, a banned pesticide that is classified as a probable carcinogen.

Other donors to the pro-labeling effort include Kent Whealy, who co-founded an Iowa group to preserve heirloom seeds, and Mark Squire, who owns Good Earth Natural Foods in Marin County. Companies with recognizable brands like Dr. Bronner's Magic Soaps, Amy's Kitchen and Clif Bar also contributed.

But the labeling proponents have been far outspent, and that appears to have hurt them. Support for the measure, which had been high in September, plummeted to 44 percent of California voters in October, according to a USC Dornsife College of Letters, Arts and Sciences/Los Angeles Times poll.

"There's no question that the money has had a tremendous impact," said Dan Schnur, director of the poll. "On the other hand, they've spent it very effectively."

Will Evans is an investigative reporter for California Watch and the Center for Investigative Reporting focusing on money and politics and government oversight. To read more California Watch stories, click here.

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  • Prop 30: Gov. Jerry Brown's Tax Initiative

    <strong>YES vote: </strong> There will be an increase in state income taxes on the wealthy (those who make over $250,000) for seven years. Sales taxes will increase by ¼ cent for four years. Its passage will stave off $6 billion in automatic “trigger cuts” -- mainly to K-12 schools and state universities -- that Gov. Jerry Brown wrote into the 2012-2013 budget. <strong>NO vote: </strong> State income taxes and sales taxes are not increased, and California's education budget will be gutted in accordance with Brown's "trigger cut" budget. <em>California Gov. Jerry Brown joins students at a rally promoting Prop. 30 in the upcoming election in Los Angeles, Tuesday, Oct. 16, 2012. Prop 30 would raise taxes, directing the money toward education. (AP Photo/Nick Ut)</em>

  • Prop 31: Two-Year Budget Cycle

    <strong>YES vote: </strong> All bills will be made public at least three days before coming to a vote before the legislature, lengthen the state's budgeting cycle from one to two years, mandate the identification of funding sources for all new programs costing over $25 million and allow local governments to create "regional collaboration" bodies possessing the ability to supersede state laws. <strong>NO vote: </strong> There will be no change to the California legislature and governor's fiscal responsibilities.

  • Prop 32: Ban On Corporate & Union Contributions

    <strong>YES vote: </strong> Unions and corporations cannot use money automatically deducted from employee checks for political donations. <strong>NO vote: </strong> There will be no change to the laws that currently allow unions and corporations to use money automatically deducted from their employees' pay checks for political purposes.

  • Prop 33: Auto Insurance Histories

    <strong>YES vote: </strong> Auto insurance companies will take into account a customer's car insurance history, even if it spans different companies. <strong>NO vote: </strong> Auto insurance companies will continue to be prohibited from giving customers discounts based on their histories with other companies.

  • Prop 34: Repeal Of The Death Penalty

    <strong>YES vote: </strong> The death penalty will end in California. <strong>NO vote: </strong> California's death penalty sentence remains intact.

  • Prop 35: Human Trafficking Penalties

    <strong>YES vote: </strong> Prosecutors will be able to seek harsher penalties (fines and prison sentences) for convicted human traffickers. <strong>NO vote: </strong> The laws currently in place about sentencing convicted human traffickers will remain intact.

  • Prop 36: Repeal Of The 'Three Strikes' Law

    <strong>YES vote: </strong> Convicts with two prior convictions who commit a third, nonserious or non-violent crime will not be sentenced to life in prison. Those who are currently in jail with a life sentence for a nonserious or non-violent crime could be given shorter prison sentences. <strong>NO vote: </strong> California's "Three Strikes Law," in which felons could receive life imprisonment for their third conviction, remains intact. Those already in jail for their third felony will remain.

  • Prop 37: GMO Labeling

    <strong>YES vote: </strong> Companies will be required to put labels on all food with GMOs (genetically modified organisms). <strong>NO vote: </strong> Genetically engineered foods will continue to remain unlabeled.

  • Prop 38: Molly Munger's Tax Initiative

    <strong>YES vote: </strong> All Californians will have a higher rates of personal income taxes, the revenues of which get routed to local K-12 schools and early childhood programs. <strong>NO vote: </strong> Californians continue with their current personal state income tax rates. Schools get no extra money. <em>Molly Munger, a wealthy attorney and civil rights advocate, listens to a reporters question regarding her proposed ballot initiative to raise income taxes for school funding following her appearance at the California Parent Teacher Association's annual meeting in Sacramento, Calif., Monday, Feb. 6, 2012. (AP Photo/Rich Pedroncelli)</em>

  • Prop 39: Income Tax Increases For Multistate Businesses

    <strong>YES vote: </strong> All businesses will be forced to calculate their taxes based exclusively on in-state sales. <strong>NO vote: </strong> Businesses will continue to choose whether to calculate their state taxes based on either the sales they make in the state or a combination of sales, property and employees in the state.

  • Prop 40: Referendum On State Senate Redistricting Plan

    <strong>YES vote: </strong> California will continue to use the new Senate district boundaries that were drawn and certified by the Citizens Redistricting Commission in 2011. <strong>NO vote: </strong> The California Supreme Court will appoint a special master to determine new state senate districts.