The general election for the Wisconsin Senate will take place on Nov. 5, 2024. Sixteen out of 33 Senate seats are up for election, including eight districts with Republican incumbents running, four districts with Democratic incumbents running, and four open districts. Republicans hold a 22-10 majority, with one vacancy. Democrats would need to gain seven seats to change partisan control of the chamber.

Wisconsin elects half of its senators to four-year terms every two years. Since this is the first year Wisconsin is holding state legislative elections under its current legislative maps, all senators will have been elected under the current districts following the 2026 elections. According to the Milwaukee Journal Sentinel, “Under the new boundaries, the state Assembly and state Senate will likely see more balance between the two parties…Under the previous maps, Republicans hold 22 out of 33 state Senate seats. Under the new state Senate map, 14 out of 33 districts are Democratic-leaning, while 15 are Republican-leaning.”

On Feb. 19, 2024, Gov. Tony Evers (D) signed Senate Bill 488 into law, adopting new Wisconsin legislative maps. Gov. Evers originally proposed the newly adopted legislative maps in 2021. Both chambers of the Legislature approved the maps on Feb. 13. The Wisconsin Senate passed the new maps 18-14, and the Assembly passed the new maps 63-33.

Ballotpedia identified four Senate battleground districts. As of Oct. 16, CNalysis identified one of these districts as a Toss-Up, one as Tilt Democratic, one as Lean Democratic, and one as Very Likely Democratic. Republicans represent all four of those battleground districts. Incumbents are running in two of these races, while the other two are in open districts, meaning no incumbents are running. Click here to read more about the battleground elections.

According to AP’s Todd Richmond, Wisconsin Democrats plan to spend seven million dollars on television ads across those five battleground Senate districts. Richmond wrote, “In a sign of how the new maps have energized the party, Democrats have put up a candidate in every Senate race on the ballot for the first time in more than 20 years…Senate Republican Majority Leader Devin LeMahieu said that voters will see the ads as another attempt by liberals to buy control of government institutions.”

Both the Republican State Leadership Committee and the Democratic Legislative Campaign Committee listed Wisconsin as a state in which they would prioritize state legislative elections this year.

Wisconsin is one of 10 states that has a divided government, since Democrats control the governorship while Republicans control both chambers of the Legislature. The outcome of the Assembly elections alone can not change Wisconsin’s trifecta status because Republicans also control the Senate. Wisconsin is one of 44 states holding state legislative elections this year.

No incumbents lost in the primaries.