Registering to vote is about to get easier for hundreds of thousands of eligible U.S. voters ahead of Election Day next year. California’s new voter registration law, enacted this week, aims to automate the process for people obtaining or renewing a driver’s license or ID card. Officials were working out the particulars of the measure, which could add up to a million voters to the rolls by 2018, California’s secretary of state said.

California's automated voter registration law is different from a similar law in Oregon, the first U.S. state to implement the idea, because residents there are automatically registered without a choice to opt out. California officials intend to make opting out as easy as checking a box.

For many years, voters in the Golden State have been able to request voter registration at state Department of Motor Vehicle offices by checking a box on an ID card or driver’s license application. But the state would then snail-mail a confirmation form, which residents had to sign and return to complete registration.

The new process eliminates the middle step, according to the Los Angeles Times. Information written on ID applications will be transmitted electronically from the DMV to the secretary of state’s office, where citizenship will be verified and eligible names will be added to voter rolls. The process will also include an “opt out” for people who do not wish to register.

The law, signed by Gov. Jerry Brown on Tuesday, goes into effect Jan. 1, 2016. The DMV and Secretary of State Alex Padilla must first develop regulations, complete a statewide database and secure the funding to implement the program, DMV officials told the Times.

That’s not a major hurdle, said Padilla, reasoning that the current state budget already funds a technology upgrade for the voter registration system. But Padilla also acknowledged that the state may not have everything in place before the June 2016 presidential primary. “At the latest, for the 2018 election cycle, I expect millions of new voters on the rolls in the state of California," he said.

California’s new law is in stark contrast to voting-related measures in some Republican-run U.S. states. When the U.S. Supreme Court gutted in 2013 a Voting Rights Act provision that regulated states with a history of voter discrimination, particularly in the South, several states passed strict voter ID laws that disproportionately affect minorities, students and the poor.

This month, in Alabama, which requires residents show a state-issued photo ID in order to cast ballots, officials announced they would close dozens of DMV offices in areas that serve mostly black Democratic voters. A group of African-American lawmakers have asked the federal government to look into the state’s decision and take action.