MADISON - The vast majority of Wisconsin voters continue to support a new law requiring anyone buying a gun to pass a background check — but their most powerful lawmakers remain opposed to the policy change.

New polling from the Marquette University Law School shows 80% of Wisconsin voters said they support expanding background checks on all firearm sales, including private and online sales — the same level of support the pollsters found in April among a different group of voters.

Such a law could have prevented a shooter in Texas from purchasing the firearm he used to kill or wound 32 people along a highway in the western part of the state.

The Wisconsin voters were surveyed just before the Texas man bought the assault rifle from a private seller, avoiding a background check. He had previously failed a review in 2014 because of a mental health issue.

The recent polling also shows support for expanding background checks among voters who own guns. Seventy-five percent of gun owners support the policy change, while 88% of people who don't own firearms want expanded checks. Among voters who refused to say whether they owned a gun, 69% supported more checks.

Gov. Tony Evers has called on lawmakers to take up a bill that would expand background checks to most firearm sales but Republican leaders of the state Legislature have all but promised to block any new rules for firearm purchases.

"There is always going to be a constituency who vote Republican and (expanding checks) means registering your firearm, and they are going to be opposed to it," Senate Majority Leader Scott Fitzgerald, R-Juneau, said earlier this month.

Aides to Fitzgerald and Assembly Speaker Robin Vos, R-Rochester, did not respond to questions Wednesday about whether the lawmakers' opinions had changed in light of the new polling and after the recent Texas shooting.

Evers, a Democrat, has said he will call lawmakers into session to take up new gun-related legislation if Fitzgerald and Vos do not advance a bill being drafted by Democratic lawmakers to expand background checks.

"It’s time for Republicans to take up universal background checks to ensure that no matter what kind of firearm someone is buying or where they’re buying it from, the process is the same for everyone," Evers' spokeswoman Britt Cudaback said in a statement.

Contact Molly Beck at molly.beck@jrn.com. Follow her on Twitter at @MollyBeck.