JEFFERSON CITY — If you thought the fight over Clean Missouri was fun, get ready for "Cleaner."

Missouri Republicans took a big step toward asking voters to undo changes they made to the redistricting process that could cost them seats with an initial vote of approval in the Senate Tuesday evening.

The voice vote came when a number of senators were not at their desks, including Sen. Lincoln Hough, R-Springfield, and Sen. Eric Burlison, R-Battlefield, so the exact margin of passage was not clear.

But if Republicans can repeat that performance on a roll call, the plan will head to a House that already approved a similar measure last year. Gov. Mike Parson, a fellow Republican, also supports the idea, which would go before voters later this year.

Senate Democrats did their best to draw out debate on the idea in the past week. In floor speeches, they accused Republicans of trying to restore gerrymandering and overturn the will of voters, who approved Clean Missouri with 62 percent of the vote in 2018.

"When we hear from the people directly, as we did in 2018, I'm going to listen," Sen. Jill Schupp, D-Creve Coeur, said.

But Republicans have never accepted that rationale, saying the voters were bamboozled by other parts of Clean Missouri like new limits on lobbyist gifts and campaign contributions meant to hide the work the amendment would do to help Democrats.

The new Republican-backed proposal also includes changes to ethics laws, such as an outright ban on lobbyist gifts to lawmakers and a $100 reduction in the amount of money donors can give to Senate candidates. The proposal would make those campaign contribution limits, which now are tied to inflation, permanent.

Senate President Pro Tem Dave Schatz, R-Sullivan, told Schupp his party is simply trying to give voters another "bite of the apple" when they go to the polls later this year.

"When this goes to the ballot, if (voters) knew exactly what they were doing, they'll reject this notion and it won't pass," he said. "But then as you said, the voters have voted, we're going to accept it, we're going to move on."

If Schatz ultimately has his way, voters will consider neutering two key changes Clean Missouri made to how the state will draw new districts for legislators after this year’s census.

The first created a new “nonpartisan” demographer to draft legislative districts. To override the demographer's recommendations, a 10-person bipartisan panel of political appointees would have to muster seven votes.

The second changes the map drawers’ priorities. In the past, they’ve focused on drawing compact shapes. Now, that takes a back seat to drawing districts more likely to produce more competitive races and better align the overall makeup of the legislature — where Republicans hold supermajorities in both houses — with the outcomes in statewide elections.

That last part is key: those elections have been a lot closer than individual statehouse races in recent years.

The resolution carried by Sen. Dan Hageman, R-Cosby, would generally restore the old system, nixing the new demographer and shifting concerns about competitive races and partisan balance to the back burner.

It could also help out his colleagues.

An Associated Press analysis found Clean Missouri's new formula really could help Democrats’ chances in 2022.

Republicans won 13 more House seats in 2018 than would be expected based on their share of votes for House candidates statewide, and the amendment's provisions are designed to reduce that kind of disparity.

It would also remove a key phrase from the constitution that guides how the map drawers count how many people live in each district to make sure they're roughly equal.

Democratic critics in the Senate on Tuesday blasted Republicans for questioning voters' 2018 decision.

"The voters made a resounding statement," Kansas City Democratic Sen. John Rizzo said during Tuesday debate.

Missouri was one of five states where voters in 2018 approved redistricting ballot measures designed to decrease the potential for partisan influence when redrawing voting districts. An Associated Press analysis of Missouri's redistricting formula shows it is likely to lead to Democratic gains in the state Legislature while dropping Republican supermajorities closer to the more even partisan division often reflected in statewide races.

Democrats say that could lead to map drawers ignoring immigrants, children and people who don't vote, which could punish cities and suburbs where Democrats tend to do well.

Republicans have largely brushed off those concerns, telling reporters last week that the courts would decide any dispute on that matter, according to the Post-Dispatch.

Neither the 2018 measure nor the new Republican proposal affects redistricting for the U.S. House, which would continue to be passed as a bill by state lawmakers subject to a gubernatorial veto.

The Associated Press contributed to this report.

Austin Huguelet is the News-Leader's politics reporter. Got something he should know? Call him at 417-403-8096 or email him at ahuguelet@news-leader.com.