A bill to block states from issuing mandatory labeling laws for products that contain genetically modified ingredients overcame a major hurdle in the Senate on Wednesday.

Supporters have hailed the legislation, which advanced 65-32, as a bipartisan compromise in the national fight over the labeling of foods that contain genetically modified organisms, better known as GMOs.

The bill allows food producers to use QR codes that consumers scan with a smartphone to find out if a product contains GMOs instead of stating on the label that the product was “produced with genetic engineering” — required by laws passed in states such as Vermont, Maine, Connecticut and Alaska.

Democrats slammed the agreement as an industry-backed bill to deny Americans the right to now what’s in their food. 

“Here is a so-called labeling bill, but in fact it does the opposite,” said Sen. Jeff Merkley (D-Ore.). “This so-called mandatory labeling bill isn’t mandatory, doesn’t label, and it excludes most GMO foods.”

During the vote, members of the Organic Consumers Association threw money from the Senate gallery in protest.

The protesters yelled “Monsanto Money” and “Sen. Stabenow, listen to the people, not Monsanto” while $2,000 fell to the floor.

Under the legislation — which defines bioengineering as food “that contains genetic material that has been modified through in vitro recombinant DNA techniques; and for which the modification could not otherwise be obtained through conventional breeding or found in nature” — Democrats claim a number of GMO foods are excluded.

“That definition means that corn oil derived from Monsanto GMO corn isn’t GMO for purposes of this bill; it means that soy bean oil derived from Monsanto GMO soy crop is not GMO for purposes of this bill; it means that sugar derived from Monsanto GMO sugar beats is not GMO for purposes of this bill — thus the main GMO crops in America are not GMO magically through the definition utilized in this bill,” Merkely said.

In technical comments, the Food and Drug Administration (FDA) took issue with the definition for the same reason, but supporters claim that very agency found no proof that GMOs are dangerous.

“I find it ironic that those who challenge this science have latched on to comments from the FDA, an agency who has found no scientific evidence that biotechnology threatens human safety as some type of credibility,” Stabenow said, warning that opponents would be “denying the overwhelming body of science” on biotechnology if they voted against the bill.

In a statement to The Hill, Monsanto called the bill a bipartisan solution to GMO labeling and claimed it has the support of more than 1,000 food, agriculture and business organizations and companies.

“The overwhelming majority of food and agriculture is voicing support for this bill with the members of the U.S. Senate,” Charla Lord, the company’s spokeswoman, said.

During a debate on the floor, Sen. Pat Roberts (R-Kan.) warned that food producers would be stuck trying to navigate a patchwork of different state laws if the legislation failed.

“If we don’t act today, what we face is a handful of states that have chosen to enact labeling requirements on information that has nothing to do with health, with safety, or nutrition,” he said. “Those labeling laws will ultimately impact consumers who will suffer from much higher priced food.” 

But opponents say it’s the obstacle course created by the QR codes allowed under the bill that will hurt consumers.

“That obstacle course means you have to have a smartphone, you have to have to be able to scan this code, you have to have a digital plan that you’re paying information for, you have to have wireless in the store and you have to take a lot of time to go to a website to find out the answer,” Merkley said.

Critics also argue that the bill lacks any language that would allow the Agriculture Department to enforce the labeling law it’s been directed to create while blocking states from taking any action of their own.

“The Roberts-Stabenow bill will pre-empt the strong GMO labeling that went into effect in Vermont a few days ago on July 1 and also undermine the efforts of other states to label GMOs,” Sen. Bernie Sanders (I-Vt.) said. “The timing of this legislation is no accident. What its goal is, is to overturn, rescind the very significant legislation that passed in the state of Vermont.”

The Democrats who voted in support of the bill included Sens. Tammy Baldwin (Wis.), Michael Bennet (Colo.), Tom Carper (Del.), Bob Casey (Pa.), Chris Coons (Del.), Joe Donnelly (Ind.),  Dianne Feinstein (Calif.), Al Franken (Minn.), Heidi Heitkamp (N.D.), Tim Kaine (Va.), Amy Klobuchar (Minn.), Joe Manchin (W.V.), Claire McCaskill (Mo.), Robert Menendez (N.J.), Gary Peters (Mich.), Jeanne Shaheen (N.H.), Debbie Stabenow (Mich.) and Mark Warner (Va.).

Updated at 7:43 p.m.