Last Friday, Bernie Sanders held a rally in a parking lot across the street from a Hollywood studio. Hillary Clinton and Donald Trump were not mentioned, nor was any other politician on the 2016 ballot. Sanders was there as part of an effort to lower runaway prescription drug prices. “The pharmaceutical industry has become a major health hazard to the American people!” Sanders thundered in front of about 500 supporters. “This is the most significant proposition in the country today to end pharmaceutical greed.”

Bernie’s crusade is known as Prop 61, and it manages to be both modest and earth-shaking, a minor element in reforming drug-purchasing that would set a critical precedent to stop price-gouging by Big Pharma. If the referendum is passed this November, the majority of Californians will see no relief other than as taxpayers; their drug prices might even rise as an indirect result. But at a time when Americans are deeply concerned about the cost of medicine, any measure with the potential to alleviate the burdens of the current system deserves support.

Written by the AIDS Healthcare Foundation, Prop 61 would require state agencies in California that make prescription drug purchases to only pay what the Department of Veterans Affairs pays. The VA enjoys the lowest prices for drugs in the nation, in part because it is protected by a federal law that prohibits it from paying above 76 percent of the average wholesale price. Polls show significant support for Prop 61, but that’s before gauging the full impact of a drug industry opposition campaign that could total $100 million, making this one of the costliest ballot measures in California history.

If Prop 61 were passed, it would affect a fairly small population. California purchases drugs for current and retired state employees, students at public universities, prison inmates, and low-income beneficiaries of Medi-Cal, the state Medicaid program. However, Medi-Cal managed care plans, which serve 75 percent of all enrollees, are exempt from the rule (probably because the AIDS Healthcare Foundation runs a Medi-Cal managed care program itself). So while California spent $3.8 billion on prescription drugs in the 2014-2015 fiscal year, Prop 61 would cover less than that.

Furthermore, the savings are hard to model. The VA does not publicly disclose how much it pays for medications; it’s assumed that it gets additional discounts beyond the federal ceiling, but nobody knows how much on every drug. State agencies would have to file a Freedom of Information Act request just to know how much to charge the drug companies, and the VA could invoke a trade secret or financial information exemption. Furthermore, the VA has a limited formulary, while Medi-Cal must offer any drug approved by the FDA. On those drugs that the VA doesn’t buy, Prop 61 will have no effect.