Wisconsin Democratic Gov. Tony Evers on Monday signed into law new maps that will shift the balance of power in a state Legislature that has been dominated by Republicans for more than a decade.

The new maps followed a change in the balance of the state Supreme Court from a 4-3 conservative majority to a 4-3 liberal edge after Janet Protasiewicz won a seat last year following the retirement of a conservative-leaning justice. In December, the court ruled that the state’s existing maps, which experts have described as some of the most gerrymandered in the country, were unconstitutional, ordering new lines to be drawn ahead of the 2024 elections.

The existing map heavily favored Republicans — who controlled 64 of 99 seats in the state Assembly and 22 of 33 in the state Senate — in a battleground state that that has seen razor-thin margins of victory in recent U.S. Senate and presidential races. According to a Milwaukee Journal Sentinel analysis, the new maps have a roughly even split of Democratic and Republican-leaning state Assembly districts, which will all but guarantee a wave of Democratic gains this fall.

“When I promised I wanted fair maps — not maps that are better for one party or another — I damn well meant it,” Evers said in a statement. “Wisconsin is not a red state or a blue state — we’re a purple state, and I believe our maps should reflect that basic fact.”

In a statement, state Assembly Speaker Robin Vos, a Republican, said the maps Evers signed were “the most Republican-leaning maps out of all the Democrat-gerrymandered maps” the state’s high court is considering.

“We sent him those maps, not because they are fair, but because the people of Wisconsin deserve certainty in state government,” Vos said. “This fall Republicans will prove that we can win on any maps because we have the better policy ideas for the State of Wisconsin.”

Ben Wikler, chair of the Wisconsin Democratic Party, described the new legislative maps as “a sea change.”

“The end of Wisconsin’s gerrymandering era will unleash a new wave of energy from candidates, volunteers, and voters that could affect not just the state legislature, but the U.S. House, the Senate, and the presidential race,” he said.

With the new maps in place, Democratic groups are already gearing up to flip seats this fall.

“Wisconsin is a top priority for the DLCC in 2024, and we’re already hard at work building the campaigns that will fuel our legislative gains this fall,” Democratic Legislative Campaign Committee president Heather Williams said in a statement. “The time for fair representation in Wisconsin is long overdue, and we are building winning campaigns and sustainable infrastructure to build power this cycle and ultimately take back both majorities.”