Drivers for gig companies like Uber and Lyft gained the right to unionize in California on Friday, thanks to a bill signed by Gov. Gavin Newsom.

The bill allows unions representing drivers to bargain for better wages and benefits and could serve as a model for other states given the size of California’s ride-hailing industry — about 800,000 drivers, according to the bill’s backers. Only Massachusetts has a similar law, which was passed through a ballot measure last year.

The bill could help resolve a yearslong fight in which driver groups have pushed for employee status, which confers protections like a wage floor and the right to unionize, while gig companies resisted. Those companies have long maintained that workers should be considered independent contractors and said that making drivers employees would upend their business models.

The California law combines elements of both approaches, preserving the idea that drivers are independent contractors while giving them the ability to bargain collectively. The companies did not oppose the bill.

“This is a historic agreement between workers and business that only California could deliver,” Mr. Newsom said in a statement after blessing the legislation in August. “Labor and industry sat down together, worked through their differences, and found common ground that will empower hundreds of thousands of drivers.”

Under the bill, if 10 percent of California’s ride-share drivers indicate their support for a union through authorization forms, the union can file for an election to represent all of the state’s drivers. Alternatively, a union could be certified to represent drivers without an election by gathering support from a majority of drivers, or from 30 percent of drivers if no other group comes forward to demonstrate 30 percent support for challenging it.