WASHINGTON — The Senate on Wednesday pushed forward a labeling bill that would require foods sold in the United States to reveal the presence of genetically modified organism, known as GMOs.

In a procedural vote that presaged almost certain passage, 65 senators — including Amy Klobuchar and Al Franken of Minnesota — agreed to close debate on legislation that would establish mandatory on-package designations of genetically engineered ingredients. That paves the way to an approval vote that needs only a simple majority to pass.

Shouts of protest from the Senate gallery accompanied the vote to close the GMO debate. They came from food labeling proponents who saw the bill as too friendly to big food and agriculture.

If passed and signed into law, the federal labeling bill will immediately ban state food labeling laws like one that took effect July 1 in Vermont and replace them with a national standard. But it will take two years to phase in.

Some Minnesota food companies and many in the state’s agriculture industry pushed for a national ban on mandatory GMO labels, as well as a ban on state laws. But a proposal to do that did not pass in March. The result was a bipartisan compromise that food and agricultural interests, as well as some consumer groups, accepted.

“This is a true example of compromise,” said Minnesota Farm Bureau President Kevin Paap, who wanted a voluntary GMO labeling standard. “Nobody got everything they wanted. But I think this package will provide consistency to consumers while protecting interstate commerce.”

Hormel has called for the bill’s passage since the compromise was announced two weeks ago. On Wednesday, the company praised the Senate for showing “strong, bipartisan support to provide American consumers with transparent, consistent, science-based product ingredient information.”

Chris Policinski, president and CEO of Land O’Lakes Inc., lobbied personally against mandatory on-package GMO labels. But in a statement Wednesday, Policinski said he was “pleased with the Senate action today to advance a more robust and transparent conversation about food.”

General Mills, which spent $2 million fighting state GMO labeling laws in California and Washington, changed its national packaging to comply with the Vermont GMO law after the March Senate vote failed. The company welcomed Wednesday’s compromise as an “additional step toward a national solution.”

Franken, Klobuchar views

Franken and Klobuchar, who both voted against the earlier labeling law, viewed the new labeling bill as a necessary compromise.

The new legislation “will help consumers know what’s in their food,” Franken said in a statement, “It’s not a perfect bill, but unlike the previous version of this legislation — which I opposed — this compromise includes a mandatory federal labeling standard, which I strongly believe is necessary for this to work.”

In a statement, Klobuchar said the new legislation creates “a national mandatory labeling standard” that avoids “subjecting our entire food supply to a patchwork of state laws.”

“Minnesota will go from having no labeling to mandatory labeling — either on the package or on your smartphone,” she said. “Consumers will have the information they need to make decisions about feeding themselves and their families.”

In Minneapolis, angry opponents of the new Senate bill vowed to make the labeling bill an election issue for Franken and Klobuchar.

“Obviously, I’m extremely disappointed,” said Right to Know Minnesota’s director, Heather Kurth Flesland, who was demonstrating at Franken’s Minneapolis office on Wednesday when the senator announced his support for the bill. “All we heard are industry talking points.”

In addition to the two-year phase-in, groups like Center for Food Safety and Food & Water Watch question the bill’s definitions of genetically engineered contents and the ability of companies to use a smartphone scan code to signal the presence of GMOs. Critics say the definitions could exempt products containing genetically modified sugar beets, soybean oils and high fructose corn syrup from GMO labels. They also say words and symbols on food packages are less confusing than digital product codes.

Earlier House action

The House passed a bill earlier this year that banned a national mandate. Whether it will accept the Senate’s terms is unclear. But for those who want more, not less, GMO disclosure, the last hope may lie in the White House. Chances there are better than in the House of Representatives, but the Obama administration has so far ceded decisions about GMO labeling to the U.S. Food and Drug Administration, which has not supported mandatory labels.