Voters in Colorado on Tuesday were rejecting a grass-roots measure that called for new labeling laws for genetically modified organisms, while a similar initiative in Oregon was too close to call.
With 84% of the vote in, Colorado's Proposition 105 was losing 68% to 32%.
In Oregon, the divide over Measure 92 was far narrower -- 51% against and 49% for -- with 68% of the votes counted.
The proposals in both states pitted a coalition of organic farmers and nutrition activists against leading food manufacturers, including Monsanto Co., Kraft Foods Group Inc. and Coca-Cola Co.
Both measures called for food labeling to identify materials that have been genetically engineered or modified. Supporters argued that consumers were entitled to know what their food contains, while opponents claimed such labeling would stigmatize their products.
A GMO is any plant or animal that has been modified with outside DNA, a method used to increase yields or provide protection against diseases.
The states were vying to become the first to pass such a referendum, hoping to do what Washington and California could not accomplish after expensive campaigns in 2013 and 2012, respectively. Vermont lawmakers approved such labeling, but the issue is still being fought in the courts.
There are persistent concerns that what some call "frankenfood" has hidden dangers, although a 2008 report by the National Academy of Sciences found no health problems associated with GMOs.
Many called the battle a David-versus-Goliath faceoff, with grass-roots coalitions that supported the labeling measures being far outspent by the major corporations that opposed it. In Colorado, for example, labeling supporters raised at least $700,000, compared with an estimated $12 million for opponents.
In Oregon, the campaign over Measure 92 became the costliest in the state's history. Monsanto donated more than $4 million to defeat the masure, it was reported. On the other side, Dr. Bronner's Magic Soaps, which has supported similar labeling battles elsewhere, gave $1.1 million.
Just before election day, opponents argued that labeling measures would actually hurt the people they were designed to help.
"We oppose state-by-state mandatory labeling laws like Measure 92 in Oregon and Proposition 105 in Colorado," Monsanto spokesman Thomas M. Helscher said in an email to the Los Angeles Times. "They don't provide any safety or nutrition information and these measures will hurt, not help, consumers, taxpayers and businesses."