Wisconsin’s “Core Four” Taxpayer Battlegrounds

Control of the Wisconsin State Senate could come down to these four competitive districts this November, and the tax policy differences in those races could not be clearer.

Republicans currently hold an 18-15 Senate majority. Senate President Pro Tempore Patrick Testin has dubbed the Republican candidates in four critical districts the “Core Four”: Mike Roberts in District 5, Sen. Howard Marklein in District 17, Jim Croft in District 21, and Michele Skinner in District 31.

With Milwaukee County Executive David Crowley leading the Democratic ticket for governor against Republican Congressman Tom Tiffany, these four Senate races could have major consequences for Wisconsin taxpayers.

Here is what is at stake.

District 5: Mike Roberts vs. Robyn Vining

Small business owner Mike Roberts has made lowering Wisconsin’s tax burden a central part of his campaign. 

Roberts supports lowering property taxes, returning Wisconsin’s state surplus directly to taxpayers, and cutting regulatory restrictions by 15 percent over three years. He has also called for lower income taxes and wants Wisconsin out of the top ten states for highest property-tax burden.

Roberts has also made ending Gov. Evers’ 400-year veto a priority, arguing that the policy is putting upward pressure on property taxes.

His opponent, Democratic state Rep. Robyn Vining, has taken a very different approach in Madison.

Vining voted against a constitutional amendment that would prevent Wisconsin governors from using the partial veto to create or increase taxes or fees. She also abstained on legislation exempting qualifying tipped income from the state income tax and voted against legislation extending tax benefits for apprenticeship and trade-school tuition.

For District 5 taxpayers, the contrast is clear: Roberts is campaigning on lower income and property taxes, while Vining’s record includes opposition to several efforts aimed at limiting or reducing Wisconsin’s tax burden.

District 17: Howard Marklein vs. Jenna Jacobson

Sen. Howard Marklein has represented Wisconsin’s 17th Senate District since 2015, giving taxpayers more than a decade of votes and legislative accomplishments to judge him by.

During his time in the Senate, Marklein has built an extensive record of delivering tax relief. As co-chair of the Joint Finance Committee, he helped advance the 2025-27 state budget containing roughly $1.3 billion in income tax cuts. He has also supported eliminating Wisconsin’s sales tax on residential electricity and using the state surplus to provide property-tax relief and return money to taxpayers.

When Evers proposed raising the top income tax bracket, Marklein was essential in rejecting this proposal in the Joint Finance Committee. He has also been at the center of efforts to reverse Evers’ 400-year veto.

His opponent, Democratic state Rep. Jenna Jacobson, has opposed several recent tax-relief efforts. Jacobson voted against legislation exempting overtime pay from Wisconsin’s income tax. She has also called for increased state spending on public schools, repeatedly arguing that Wisconsin schools have been “under-funded” and need additional taxpayer resources.

District 21: Jim Croft vs. Trevor Jung

Small business owner Jim Croft has centered his campaign on lowering costs for Wisconsin families and businesses. Croft supports lower taxes and property-tax relief, arguing that rising property taxes are making it increasingly difficult for Wisconsin families to get by. He has called for bringing down taxes “across the board” and reducing unnecessary regulations that drive up the cost of goods and services. Croft has also made cutting taxes and holding the line on the growth of state government spending among his top budget priorities.

His Democratic opponent, Trevor Jung, is running on a substantially different fiscal agenda. Jung is in line with David Crowley’s tax policies, which would only lead to higher costs for working families. 

District 31: Michele Skinner vs. Jeff Smith

Michele Skinner is challenging incumbent Democratic Sen. Jeff Smith with tax relief at the center of her agenda.

Skinner supports cutting Wisconsin income and property taxes and returning excess state funds to taxpayers. She has pledged to fight rising costs and points to her work on the Eau Claire County Board as evidence of efforts to reduce the burden on local taxpayers while maintaining essential services.

Smith’s record in Madison provides a sharp contrast. Smith opposed the 2026 surplus package that included property-tax relief, taxpayer rebate checks, and eliminating state income taxes on qualifying tips and overtime. He also voted against overriding Evers’ 400-year veto and opposed efforts to restore roughly $3 billion in income tax cuts after Evers vetoed most of the original reduction.

Smith has also repeatedly pushed to expand BadgerCare, including proposals that would expand government healthcare coverage and bring billions in additional federal spending into Wisconsin.

Four Races, One Taxpayer Divide

The stakes in these four races extend far beyond their individual districts.

David Crowley brings a record of tax increases to the governor’s race. As Milwaukee County Executive, Crowley signed an 80 percent increase in the county sales tax rate, from 0.5 percent to 0.9 percent. Crowley’s proposed 2026 county budget called for hiking the property-tax levy by approximately $12 million. Now, Crowley supports raising taxes on millionaires and has called for a “holistic” look at Wisconsin’s tax system.

Crowley’s record and tax proposals make control of the State Senate especially consequential. The next Senate will have a major say in whether future tax-and-spending proposals advance in Madison.

The “Core Four,” meanwhile, have emphasized a different direction: lower income and property taxes, returning surplus revenue to taxpayers, reducing regulatory burdens, and ending Evers’ 400-year veto. Their Democratic opponents have opposed major tax-relief measures or called for greater government spending.

Wisconsin taxpayers could therefore face two very different directions in 2027. The state can continue pursuing tax relief and returning surplus dollars to taxpayers, or move toward the higher-tax, higher-spending policies Crowley and Democrats have supported.

With control of the Senate hanging in the balance, Wisconsin’s “Core Four” races could determine whether taxpayers get another round of relief or face a new push for higher taxes in Madison.