MADISON - Opponents of gerrymandering vowed to put nonpartisan redistricting on the front burner Tuesday as they acknowledged their chances of passing legislation on the issue were slim.

Backers of the plan said at a Capitol news conference they have public sentiment on their side and would use it to get support from more lawmakers.

"Even if they don't put this bill on the floor, we’re going to keep the pressure on," said Sachin Chheda, director of the Fair Elections Project. "We're going to be knocking on doors and all across the state for the next year and a half. We're going to make sure that people understand who is rigging the maps and who wants change."

Republican legislative leaders oppose the bill, which would require civil servants to draw legislative and congressional districts in ways that wouldn't give one political party an advantage. Supporters of the bill conceded it would be difficult to get a hearing for the legislation, let alone a vote on it.

Just three Republicans — Reps. Joel Kitchens of Sturgeon Bay, Todd Novak of Dodgeville and Travis Tranel of Cuba City — have signed onto the legislation.

Every 10 years, states must draw new election maps to account for changes in population. Republicans controlled all of Wisconsin's government in 2011 and established maps that have helped them hold onto large majorities.

Those at Tuesday's news conference called gerrymandering a bipartisan problem, noting Democrats drew maps to their advantage in states where they were in charge.

"Partisan gerrymandering is wrong when Democrats do it and it's wrong when Republicans do it," said Rep. Robyn Vining, a Democrat from Wauwatosa.

Assembly Speaker Robin Vos of Rochester made clear the legislation is going nowhere.

"Rather than handing over our constitutional duty to an unelected, unaccountable board of bureaucrats appointed by politicians, redistricting should continue to be the responsibility of the Legislature and governor," Vos said in a statement.

He said Democrats were pushing for redistricting reform because of "sour grapes."

A Marquette University Law School poll in January found 72% of Wisconsin voters support having a nonpartisan commission draw the maps. Majorities of both parties backed that idea.

The Democrats who held Tuesday's news conference repeatedly praised the three Republicans who have signed onto the legislation, but said they didn't know why they weren't at the event. Novak and aides to Kitchen and Tranel said they hadn't been invited to the news conference.

“When I first ran for office in 2014, I supported nonpartisan redistricting reform," Novak said by email. "In each session since, I have cosponsored legislation creating a nonpartisan process. I proudly support this bill and the creation of a nonpartisan redistricting process."

Supporters of the Wisconsin legislation are making a renewed push for the bill after the U.S. Supreme Court determined this month that federal courts can't hear cases on whether maps are tilted too heavily in one party's favor.

The decision stemmed from cases from North Carolina and Maryland. Days later, Democratic voters challenging Wisconsin's maps acknowledged the Supreme Court decision meant the end of their case and sought to drop it.

On Monday, attorneys for Wisconsin Republicans asked a panel of federal judges to force the voters who brought that lawsuit to pay some of their legal bills.

They did not say how much they are seeking but asked for the fees to be covered since January. They argued Wisconsin's case should have been put on hold at that point because that's when the Supreme Court scheduled arguments in the cases from the other states.

The Wisconsin legislation would require the nonpartisan Legislative Reference Bureau to draw maps without giving either side an advantage and without accounting for incumbency.

The reference bureau would report to a five-member advisory commission. The commission would consist of two Democrats and two Republicans and those four members would then choose a fifth member, who would serve as the commission's chairperson.

The maps drawn by the reference bureau would be presented to the Legislature for approval and lawmakers initially could not make changes to them.

If lawmakers were unable to pass the maps as drawn by the reference bureau, they would eventually be able to tweak them, but in that case they would need to get three-fourths majorities in both houses to approve them.

The legislation is modeled on an Iowa law that advocates of redistricting reform have long championed.

Contact Patrick Marley at patrick.marley@jrn.com. Follow him on Twitter at @patrickdmarley.