The U.S. House advanced legislation designed to let banks do business with cannabis companies in states that permit marijuana sales, a step that some supporters see as helping to pave the way to nationwide legalization.

The Secure and Fair Enforcement Banking Act, which passed on a 321-103 vote on Wednesday, would protect lenders from federal punishment for doing business with firms in the burgeoning industry. The bill won bipartisan support in the House amid calls to help cannabis companies move away from being all-cash operations.

The legislation co-sponsored by Democrats Ed Perlmutter of Colorado and Denny Heck of Washington is meant to allay national banks’ fear of doing business with cannabis companies because federal law makes it illegal for them to accept cash deposits, process credit-card payments, clear checks or make loans.

With House passage, the next move is up to the Senate, where the measure would need to overcome Republican resistance. Even if it passes there and is signed into law President Donald Trump, the new safeguards aren’t likely to draw big banks into pot banking, according to Cowen analyst Jaret Seiberg.

“This is not a total victory,” Cowen said in a note before the House vote. “The biggest banks that operate across state lines will still worry that cannabis is still illegal at the federal level.”

SAFE Act supporters say banks’ resistance to pot business has created a public safety problem in which thousands of growers, retailers and employees are awash in cash and thus more vulnerable to crime.

Small banks and credit unions, meanwhile, see the current situation as a missed opportunity as more states legalize marijuana and businesses boom. In the past year, lobbying groups including the American Bankers Association have pushed for legislation to amend the rules, which has helped attract Republican support.

“This bill will help banks meet the needs of their communities while reducing cash-motivated crimes, increasing the efficiency of tax collections and improving the cannabis industry’s financial accountability,” the ABA said in a statement after the vote. “It will also ensure that businesses with indirect ties to the cannabis industry -- including vendors, utility companies and law firms -- won’t be needlessly forced out of the financial system.”

Changes were made to the House version to help sway key lawmakers. One is a hemp provision aimed at Senate Majority Leader Mitch McConnell of Kentucky, whose state is a major grower of the non-intoxicating form of cannabis. Senator Mike Crapo, the Idaho Republican who leads the Banking Committee, has said he hopes to take up the issue and hold a vote later this year.

Senator Cory Gardner, a Colorado Republican, has played a key role in drumming up support for the bill. He’s up for re-election next year, and his seat could be crucial for maintaining Republican control of the Senate.

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