More than 4 million Californians voted for a label, but that amounted to only 46 percent of voters while 53 percent opposed.
David Murphy with Yes on 37 says the California campaign succeeded in drawing national attention.
MURPHY: "This is a social movement, and building awareness about an issue, genetically-engineered foods, it wasn't even on the on map five years ago, politically, in a national conversation."
Murphy says the California initiative engaged over 10,000 volunteers. Stacy Malkan is with Yes on 37.
MALKAN: "It did build an organizing force that's ready to go forward, with just so much passion and energy."
The organizers are funneling that energy into passing labeling initiatives in Washington state and Oregon, and rallying to push legislation in Connecticut and Vermont.
A coalition of consumers groups and organic farmers is also pressuring the Food and Drug Administration for national labeling regulations.
The issue could be pushed to the forefront if the FDA
approves a variety of genetically-engineered salmon.