A sense of urgency pervades the debate.

The Safe and Accurate Food Labeling Act of 2015, H.R. 1599, which was passed by the House of Representatives by a lopsided, bipartisan vote of 275 in favor versus 150 against on July 23, is looking for Senate champions. After passage in the House, the bill was reported to the Senate on July 24 and referred to the Senate Committee on Agriculture, Nutrition and Forestry for consideration.

The Safe and Accurate Food Labeling Act as passed by the House states the Food and Drug Administration must allow, but not require, genetically engineered food to be labeled as G.M.O. (genetically modified). It also would preempt state and local restrictions on G.M.O.s or G.M.O. food and labeling requirements for G.M.O.s, G.M.O. food, non-G.M.O. food, or "natural" food.

The act also would require a developer of a bioengineered organism intended for use in or as food to submit a premarket biotechnology notification to the F.D.A. The pre-market notification must include the developer's determination that food from, containing, or consisting of the G.M.O. is as safe as a comparable non-G.M.O. food. For the G.M.O. to be sold as food, the F.D.A. must not object to the developer's determination. If the F.D.A. determines there is a material difference between a G.M.O. food and a comparable non-G.M.O. food, the F.D.A. may specify labeling that informs consumers of the difference.

A food label may only claim that a food is non-G.M.O. if the ingredients are subject to certain supply chain process controls. No food label may suggest that non-G.M.O. foods are safer than G.M.O. foods. A food may be labeled as non-G.M.O. even if it is produced with a G.M.O. processing aid or enzyme or derived from animals fed G.M.O. feed or given G.M.O. drugs.

The act has broad support in the food industry, which is seeking to avoid a patchwork of local and state laws requiring mandatory labeling of G.M.O. foods.

Indications were Senator John Hoeven of North Dakota, a Republican, may introduce a Senate companion bill to H.R. 1599. Mr. Hoeven is a member of the Senate Agriculture Committee and is chairman of the committee's subcommittee on nutrition, specialty crops and agricultural research. There were no indications as yet who might be a Democrat co-sponsor.

A spokesman for the Grocery Manufacturers Association said, "Currently we're in discussions with a number of Senate offices, and we look forward to working with Senator (Pat) Roberts (of Kansas) and others to move this bill forward for passage this year."

The House bill was introduced by Representative Mike Pompeo of Kansas, a Republican, and Representative C.K. Butterfield of North Carolina, a Democrat. Forty-five House Democrats voted in favor of H.R. 1599, including Mr. Butterfield and Representative Collin Peterson of Minnesota, the ranking member on the House Committee on Agriculture.

To build support for the House G.M.O. labeling bill during the congressional August recess, the Coalition for Safe Affordable Food released radio and television advertisements in Kansas, home to both Mr. Pompeo and Mr. Roberts, chairman of the Senate Agriculture Committee, and Minnesota, home to Mr. Peterson.

"Across the country, misguided politicians have threatened policies that could hurt our environment, close family farms, and increase food prices by $500 per family," said the advertisement aired in Kansas. "But Congressman Mike Pompeo is fighting for a solution that would keep food prices down, help farmers, and protect our environment. Call Congressman Pompeo and tell him to keep fighting for the Safe and Accurate Food Labeling Act. It's the right thing for Kansas and for our country."

Claire Parker, a spokeswoman for the coalition, said of the advertisements, "This is a great opportunity for us to thank Representative Pompeo for his leadership. We look forward to working with him and Senator Roberts to get this legislation signed into law."

Ms. Parker said the coalition was confident as the Senate takes up the bill.

"The strong bipartisan vote in the House gives us momentum," she said. "And members of Congress are aware of the urgency to act. The Vermont (mandatory G.M.O. labeling) law goes into effect next year, and food companies are having to make plans now on what they must do." The message: Time is of the essence.

For his part, Mr. Roberts told the Topeka Capital-Journal, "I expect that we will be discussing biotechnology issues in the Agriculture Committee in the near future."

Mr. Roberts said he was pleased Mr. Pompeo addressed the issue of G.M.O. labeling.

"I understand there are different approaches to provide consumers with more information about their food, and I am watching this issue very closely," he said. "It is important that any federal legislation on this topic consider scientific fact and unintended consequences before acting."