The legislation says nothing in the bill prevents states from enacting legislation to test people who want SNAP benefits for illegal drug use. It also lets states block eligibility for SNAP for those people who fail a drug test.

That language is similar to a farm bill amendment the House approved in June. Just before that vote, Democrats said drug testing would humiliate people trying to get help under the SNAP program.

However, the House approved the amendment by voice vote, and no Democrat asked for a recorded vote.

The bill also terminates the U.S.-Mexico Partnership for Nutrition Assistance Initiative. GOP critics of promoting U.S. nutrition programs to Mexicans living in the United States. Republican critics say this partnership promotes SNAP to Mexicans living in the United States, and charge that it allows the U.S. to promote the possibility of accessing food stamps to Mexicans who might emigrate to the United States.

Republicans have been looking for ways to trim the multi-billion dollar cost of the federal food stamp program, formally known as the Supplemental Nutrition Assistance Program (SNAP). The bill includes a $20 billion cut to SNAP that is achieved by ending automatic eligibility for the program, along with other reforms — this language was already in a farm bill Republicans proposed earlier this year.

But it also includes another $20 billion cut that is achieved by eliminating a waiver that allows states to give able-bodied adults access to SNAP benefits after three months, even if they do not meet the law's work requirements.

— This story was updated on Sept. 18, at 11:26 a.m.