Effects of Cost and Campaign Advertising on Support for California’s Proposition 37

Proposition 37 would have required genetically engineered food in California to be labeled. This paper reports the results of a survey designed to determine Californians’ voting intentions prior to the vote, perceptions about the prevalence of genetically engineered foods in the United States, willingness to pay for a mandatory label, and effectiveness of advocacy advertising. Overall, Californians had inaccurate knowledge about the prevalence of genetically engineered foods, and stated they were willing to pay up to 13.8% higher food costs on average for a mandatory label. Findings suggest that the effectiveness of opposition advertising was likely a formative factor in the defeat of Proposition 37.