Diane Hendricks Fuels GOP Cash Edge In Fight For Wisconsin Legislature

The Wisconsin State Capitol on Monday, July 14, 2025, in Madison, Wis. Angela Major/WPR

Campaign committees defending Republican majorities in the Wisconsin Assembly and Senate have outraised and outspent their Democratic opponents thanks to nearly $8 million in donations from billionaire Diane Hendricks.

For roughly 15 years, Republicans have controlled the Assembly and Senate. Thanks to new legislative voting maps and President Donald Trump’s historically low approval ratings, Democrats have been clamoring to flip both chambers of state government this November. The latest state fundraising reports from four groups dedicated to helping the parties win the chambers hint at their strategies.

GOP megadonor Diane Hendricks betting heaviest on Assembly Republicans

The Republican Assembly Campaign Committee posted dominant numbers between July 1 and Sept. 23. The group raised around $6.2 million, with $5.5 million coming from ABC Supply founder Diane Hendricks.

Because the committee had plenty of cash leading into the reporting period, it was able to spend around $14.3 million during that period. Of that, the group spent millions on in-kind media buys and campaign mail for several GOP candidates and incumbents:

• 61st District incumbent Rep. Bob Donovan, R-Greenfield: 767,977.51
• 88th District incumbent Rep. Benjamin Franklin, R-De Pere: $627,340.60
• 53rd District candidate David Daniels: $617,898.60
• 85th District incumbent Rep. Pat Snyder, R-Weston: $603,619.36

Notably, the Republican committee spent around $509,000 to bolster 30th Assembly District incumbent Rep. Shannon Zimmerman, whose challenger Kevin Knoke is getting assistance from national Democrats.

The Assembly Democratic Campaign Committee reported raising around $6 million between July 1 and Sept. 23. The biggest donations came from relatives of the late vice chairman of Berkshire Hathaway, Charlie Munger. Munger’s daughter-in-law gave the Democratic Assembly committee $2.5 million, while Munger’s daughter, Wendy, gave $1 million. Lynde Uihlein, a cousin of GOP megadonors Richard and Elizabeth Uihlein, gave the group $250,000.

The Assembly Democratic committee reported spending around $3 million during the period. It sent $375,000 to the Democratic Party of Wisconsin’s main account and sent $12,000 to Dan Bukiewicz, who is running for the 21st Assembly District.

Democrats outspending Republicans in competitive open Senate district races

In the state Senate, which is currently controlled by an 18-15 Republican majority, both parties are focusing on a handful of competitive races that will determine whether the chamber flips this fall. There are notable differences in their strategies.

The Committee to Elect a Republican Senate, or CERS, raised $2.3 million during the roughly three month reporting period, with $1.75 million of that coming, again, from Hendricks. The State Senate Democratic Committee, or SSDC, reported raising around $1.2 million, with $500,000 coming from Sarah O’Neill and $100,000 coming from Lynde Uihlein.

The Republican Senate committee spent nearly $2.7 million, which includes big in-kind media purchases in three races key to saving the party’s majority.

In the 31st Senate District, which Democrats are keen on holding as the party tries flipping the chamber, the Republican committee spent around $865,000 on Republican candidate Michele Magadance Skinner, while the Democratic committee spent $115,000 backing 31st District incumbent Jeff Smith, D-Brunswick.

The Democratic Senate committee was most focused on the 17th Senate District, which is held by incumbent Sen. Howard Marklein, R-Spring Green. The committee transferred around $1.6 million to Marklein’s challenger, State Rep. Jenna Jacobson, D-Oregon. The Republican Senate group spent around $224,000 backing Marklein.

In the 21st Senate District race for the open seat left vacant by Republican Sen. Van Wanggaard’s retirement earlier this year, the SSDC sent around $725,000 to Democratic candidate Trevor Jung, while the CERS spent around $210,000 on GOP candidate Jim Croft.

GOP outspending Democrats in battle for Wisconsin Legislature was originally published by Wisconsin Public Radio.