A barrage of questionable advertising, fueled by millions of dollars from giant biotech and agriculture corporations, has eviscerated support for Proposition 37, an initiative that would require labeling of genetically-modified food (GMOs).

Prop. 37 is still favored by voters 48.3% to 40.2%, according to a poll by the California Business Roundtable and Pepperdine University's School of Public Policy. But that is a dramatic narrowing of the 44-point lead (66.9% to 22.3%) supporters enjoyed two weeks ago.

Since the last survey, opponents of Prop. 37 have rolled out an advertising campaign that 40% of those polled said they had seen. It includes farmers complaining that food prices will rise and a Stanford University think tank researcher warning of special-interest loopholes. The latter ad was pulled and retooled when it was pointed out that Stanford does not allow consultants to use a Stanford ID, and that the researcher actually worked for the conservative Hoover Institution that is housed on the campus but is not part of the university.

The Sacramento Bee analyzed a radio advertisement from Prop. 37 foes and rated it “somewhat misleading.” The Bee said the ad’s claim that Prop. 37 is “a food labeling scheme written by trial lawyers to benefit trial lawyers” is false; they didn’t write it. The ad also greatly exaggerated red-tape cost estimates of the initiative by the state Legislative Analyst’s Office and relied solely on its own studies to project huge costs for consumers.

GMO labeling has a history of polling very well among the public when it is isolated from advertising blitzes. An October 2010 survey by Thomson Reuters PULSE showed that 93% of Americans wanted genetically-modified foods to be labeled. 

Prop. 37, one of 11 initiatives on the ballot, would require labels on most processed food by 2014 identifying any ingredients from agricultural products with genetically altered DNA. Food and alcohol in restaurants would be exempt, as would food from animals that have been eating the modified ingredients.

So far, the No on Prop. 37 campaign has outraised supporters $34.6 million to $5.5 million. Monsanto has been the chief contributor ($7.1 million) to No on Prop. 37, followed by Dupont ($4.9 million), BASF Plant Science ($2 million), Bayer Cropscience ($2 million) and Dow Agrosciences LLC ($2 million). Five more corporations have each contributed at least $1 million each.

Only one supporter of the proposition, Mercola.com Health Resources LLC ($1.1 million), has made a seven-figure contribution. 

Supporters of the initiative say that transparency would engender trust in the food system among consumers and provide information for future discussion of technology that is still in its early stages. Critics of the labeling law say consumers are being unnecessarily alarmed about technology that has not proved harmful. They argue that the law would be costly to implement and could generate expensive, time-consuming lawsuits.

Dozens of countries have some form of GMO labeling, but the U.S. Senate defeated a GMO labeling amendment to the sprawling federal farm bill on a bipartisan 73-26 vote after a vigorous lobbying effort led by Monsanto.

–Ken Broder

To Learn More:

Ad Blitz Pummels Support for California GMO-Labeling Proposal (by Lisa Baertlein, Reuters)

Support Drops for Measure on Labeling of Genetically Modified Food (by Marc Lifsher, Los Angeles Times)

Monsanto Leads the Charge against GMO Labeling (by Ken Broder, AllGov California)

TV Ad against Food Labeling Initiative Proposition 37 Is Pulled (by Marc Lifsher, Los Angeles Times)