MADISON, Wis. (CBS 58) -- Voters overwhelmingly approved a ballot measure to add Wisconsin's voter ID requirement to the state constitution.

State law already requires voters to show proof of an ID before casting a ballot, but the proposal will make it harder for courts to strike down the law or for lawmakers to amend it by adding language to the state constitution.

Republican lawmakers who brought the proposal to the ballot say the constitutional changes will protect the law from legal challenges in wake of the state Supreme Court gaining a 4-3 liberal majority in 2023.

The state's voter ID law has withstood numerous legal challenges since it was enacted in 2011. There's currently no pending lawsuit before a court, but some predict there could be another legal challenge in the future.

This marked the sixth time voters were asked to amend the constitution over the last year.

Since 2023, Republican lawmakers have approved eight amendments to be placed on ballots statewide. A majority of those passed, with two failing.

To take effect, Wisconsin constitutional amendments must pass two consecutive legislative sessions before the voters weigh in.

Democratic Gov. Tony Evers has no role in approving or rejecting constitutional amendments.

Other amendments that have been passed by voters addressed bail reform, election administration and funding, and prohibiting noncitizens from voting.