A referendum in Washington state on labels for foods containing genetically engineered ingredients appears headed for defeat, a relief for food companies in Minnesota and elsewhere that worked to defeat it.

But the measure's supporters, including a Minnesota-based consumers group, say the fight's not over: State-by-state labeling campaigns will continue to surface.

The Washington measure was failing 55 percent to 45 percent Wednesday, although vote counting was incomplete. The referendum was the costliest in the state's history, as money — particularly from biotech and food industries — poured in to fund advertising. Minnesota's General Mills, Cargill, Hormel Foods and Land O'Lakes all contributed.

Most corn, soybeans and sugar beets raised in the U.S. spring from genetically engineered seeds. Federal safety regulators have approved the technology and it has the imprimatur of several science groups. But suspicions over its safety remain, spurring campaigns for labeling.

"It obviously seems the voters in Washington have rejected this costly and complex measure," said Louis Finkel, head of federal affairs for the Grocery Manufacturers Association, a trade group. Its members argue that labeling would raise costs by forcing companies to make labeling runs for an individual state, or to substitute costlier ingredients that are not genetically engineered.

Mandatory labeling is also misleading, Finkel said, because food labeling should be required only for nutrition or safety, and genetic engineering technology has passed government safety tests.

But Ronnie Cummins, head of the Minnesota-based Organic Consumers Association, said polls have repeatedly shown that many consumers want to know if their food has genetically engineered ingredients. They don't believe genetic science is conclusive, he said, "and want to protect themselves from the hazards."

The Organic Consumers Association has been instrumental in pushing the vote in Washington and a similar referendum last year in California that also failed. The association contributed several hundred thousand dollars to the Washington effort, part of $7.7 million raised overall by pro-labeling forces through Oct. 30, according to MapLight, a nonpartisan research group.

Labeling opponents in Washington ponied up $22 million, led by biotech giant Monsanto with $5.4 million. PepsiCo was the biggest food industry contributor, with $2.4 million, according to MapLight. General Mills was the sixth overall largest donor in the anti-labeling camp, contributing $869,271.

Arden Hills-based Land O'Lakes contributed $144,878; Minnetonka-based Cargill, $143,133, and Hormel, $76,803.

In a statement to the Star Tribune, General Mills said "voters understand the issue, and they understand that different labels in different states based on differing standards would not be a good system."

General Mills advocates a national standard, though one for labeling non-genetically engineered food products — not a regulation for labeling foods containing genetically engineered ingredients. The Grocery Manufacturers Association is for a federal solution, too.

So are some labeling advocates — but only if a federal rule has the same teeth as standards like the ones turned down in Washington and California.

"It's always been our hope that the food industry would work with consumer advocates and the [U.S. Food and Drug Administration] toward a national solution," said Scott Faber, executive director of Just Label It, a pro-labeling group. Until then, "we expect this fight to continue to be engaged at state capitols across the country."