https://daily.jstor.org/what-the-history-of-food-stamps-reveals/

The Food Stamp Act of 1964 expanded the program. Much of its support came from farm state senators, including George McGovern, a South Dakota Democrat, and Robert Dole, a Republican from Kansas.
Then-Senator Robert Kennedy took highly-publicized tours of the Mississippi Delta to shed light on the plight of America’s hungry. In 1968, a study titled Hunger USA generated public concern.

The biggest expansion in the food stamps program came during the Nixon administration. In his first message to Congress, Nixon argued that he was determined “to put an end to hunger in America for all time.” By 1971, commodity distribution was largely abandoned in favor of food stamps, which allowed the poor themselves to make decisions about the food they purchased. By the end of Nixon’s term, the program had expanded. But media accounts of college students relying on the subsidies to feed themselves and other accounts of apparent abuses emerged. In 1974, the program was expanded to all the counties in the United States and the