By Scott Bauer and David A. Lieb, AP

MADISON, Wis. (AP) — Wisconsin Republicans have enjoyed outsize control of the Legislature in one of the most closely divided states for a dozen years. Maintaining that power is now at the heart of a drama involving the state Supreme Court that has national political implications.

A new liberal tilt to the court is driving Republican fears of losing their large legislative majorities, which were built under some of the most gerrymandered political maps in the country. Republicans have threatened to impeach the justice who was elected in April and flipped the court to a 4-3 liberal majority, unless she withdraws from any case involving redistricting. The GOP is citing concerns about her campaign statements and fundraising.

Democratic leaders have decried that threat as “political extortion” and are mobilizing voters to pressure Republicans in districts won by the new justice and to back down.

“Impeachment is an act of pure power politics,” said Ben Wikler, chair of the Wisconsin Democratic Party. “It’s a desperate gambit to avoid accountability to voters who choose their state representatives, their state senators and their Supreme Court justices.”

Altering the makeup of the Wisconsin Supreme Court also holds the potential to affect the 2024 presidential election in the perennial battleground.

Four of the past six presidential contests in the state have been decided by less than a percentage point. In 2020, the state Supreme Court, then controlled 4-3 by conservatives, came within one vote of overturning Democrat Joe Biden’s nearly 21,000 vote victory over then-President Donald Trump.

Wisconsin Republicans, who hold majorities of 64-35 in the state Assembly and 22-11 in the Senate, are squarely focused on their own futures. The political maps they drew that helped them win near veto-proof supermajorities are at risk of being overturned under the newly left-leaning Supreme Court.

Two lawsuits challenging the gerrymandered maps as unconstitutional were filed the first week after the new justice was seated. The Supreme Court has yet to decide whether it will take either case.

Republicans, and even Democrats the last time they had majority control of the Legislature 14 years ago, have resisted moves to give up their power to draw electoral district boundaries.

States that have shifted responsibility for redistricting from partisan legislatures to independent commissions generally have seen a reduction in gerrymandering, in which lines are drawn in a way that expands or cements one party’s grip on power. Districts drawn by independent commissions generally result in election outcomes more closely aligned with the will of voters.

Neighboring Michigan stands as a stark example of what can happen under independent redistricting.

Republican lawmakers, who then controlled Michigan’s redistricting process, drew maps after the 2010 census that gave them an enduring advantage for the next decade. In 2020, for example, Democratic legislative candidates received a slight majority of votes, yet Republicans won a 58-52 majority in the Michigan House and a 22-16 majority in the Senate under the maps they had drawn.

Unlike Wisconsin, Michigan allows its residents to propose their own laws or constitutional amendments and put those proposals on the ballot for a statewide vote. In 2018, voters approved a citizen-led effort to take redistricting away from state lawmakers and give the task to an independent commission. That commission, which is instructed to be guided by “partisan fairness,” drew the current legislative and congressional maps after the 2020 census.

The 2022 midterm election was the first to use Michigan’s new districts, resulting in a flip of legislative control. Democratic legislative candidates received just under 51% of the total statewide votes, translating to a 56-54 House majority and a 20-18 Senate majority.

In Wisconsin, it is impossible to change the redistricting process unless lawmakers voluntarily relinquish their power. That’s because Wisconsin is among 26 states that do not allow citizens to bypass their legislature through ballot initiatives.

The result is that Wisconsin continues to operate under legislative districts shaped by Republican lawmakers, who have built lopsided majorities that do not reflect the state’s overall political leanings.

While Republicans have used partisan gerrymandering to maintain their large majorities in the Legislature, voters have elected Democrats to all but one of the statewide executive offices that are decided on a partisan basis, including governor and attorney general. They also have elected a Republican and a Democrat to the U.S. Senate — votes that also are done on a statewide basis.

“Republican leadership in Wisconsin has worked hard over the past decade to insulate themselves from the will of the voters,” said Democratic Assembly Minority Leader Greta Neubauer.

In the 2022 election, Wisconsin’s Assembly districts had the nation’s second-largest Republican tilt behind only West Virginia, according to an Associated Press statistical analysis that was designed to detect potential gerrymandering. Republicans received less than 55% of the votes cast for major party Assembly candidates, yet they won 65% of the seats.

“That’s what you call rigged,” said Democratic U.S. Rep. Mark Pocan, a former Wisconsin state Assembly member. “It’s not a Democratic or Republican issue. It shows that there’s an imbalance in the math of a 50-50 state.”

Wisconsin Assembly Speaker Robin Vos, in testimony he gave in 2021 when introducing the latest maps, noted that the U.S. Supreme Court allowed for partisanship to be a factor when drawing lines.

“Was partisanship considered as a consideration in the map? Yes,” Vos testified.

The Wisconsin Legislature “is effectively really no longer a democracy,” said Nick Seabrook, a redistricting researcher and department chair at the University of North Florida. “There is no plausible popular vote result that’s ever going to lead to anything other than a Republican majority in the Wisconsin state legislature.”

With no avenue for a public referendum and faced with Republican dominance in the Legislature, Wisconsin Democrats shifted their focus to winning a majority of seats on the state Supreme Court with the hope of overturning the maps through a legal challenge.

The election of Janet Protasiewicz in April delivered the long-sought majority on the state’s highest court that Democrats have fought to win back over the past 15 years.

Protasiewicz made her position on redistricting clear during the campaign, calling the GOP maps approved by the conservative-controlled state Supreme Court “unfair” and “rigged.” The Wisconsin Democratic Party donated nearly $10 million to her campaign. She won by 11 percentage points during an April election and took her seat in August.

Legislative Republicans immediately called on Protasiewicz to step aside from redistricting cases, citing her comments during the campaign and donations from the Democratic Party. She never said during the race how she would rule, and in the first week of September released a letter from the state commission that investigates complaints against judges that said it had dismissed ones related to her comments on redistricting.

Still, Vos continues to threaten impeachment. It is up to each justice to decide whether to recuse, and a Supreme Court rule adopted by conservative justices more than a decade ago explicitly allows justices to hear cases involving campaign donors. All but one of the current members of the court has taken money from political parties, but Republican lawmakers have voiced no complaints about conservative justices accepting money from the GOP.

Wisconsin Assembly Republican Majority Leader Tyler August dismissed the comparison.

“She has clearly prejudged the case,” he said Sept. 7 of Protasiewicz. “We’re talking about this case, this justice, and I’ll leave it at that.”

Lieb reported from Jefferson City, Missouri.