Washington (CNN) Wisconsin Gov. Scott Walker won a victory in his state's push to require voters to show government-issued identification on Monday when the Supreme Court declined to weigh in on the law.

The American Civil Liberties Union had challenged the law, but the nation's high court refused to review a federal appeals court's ruling in Walker's favor.

The decision could boost Walker's nascent presidential campaign, adding to his history of brawling with liberal interests while governing a blue-leaning state.

"This is great news for Wisconsin voters," Walker said in a statement. "As we've said, this is a common sense reform that protects the integrity of our voting process, making it easy to vote and hard to cheat."

The decision was a victory for Walker and state Republicans who'd argued for the law -- and a blow to civil rights groups that say it could disenfranchise voters like senior citizens, students and minorities who wouldn't need driver's licenses.

The voter ID law was approved by Wisconsin's legislature in 2011, but a state judge blocked its implementation, and then a federal judge declared it unconstitutional.

Last year, though, the 7th Circuit Court of Appeals reversed that decision -- and the Supreme Court opting for no further action means the law is here to stay.

After the ACLU on Monday asked the appeals court to extend a stay that until now has blocked the law's implementation through the April 7 municipal elections, to avoid last-minute confusion, state officials said they'd only implement the law after that election.

"We're pleased the state has agreed with the ACLU's position that imposing a new restriction on voters in the midst of an election is a recipe for disaster," said Dale Ho, director of the ACLU's Voting Rights Project.

"For now, the voters of Wisconsin will be able to cast their ballots free from the burdens placed on them by this law. But this should be the case for voters permanently, not just for one election," he said. "We are evaluating our next steps in the fight for the right of all Americans to vote free from unnecessary barriers."