By Shereen Siewert | Wausau Pilot & Review

Wausau voters have elected challenger Doug Diny as the city’s next mayor by a margin of more than 400 votes, upsetting the incumbent who spent the last four years in office.

Incumbent Mayor Katie Rosenberg and Dist. 4 Alder Doug Diny battled for votes in what appears to be the most expensive mayoral race in Wausau history. The most recent campaign reports only cover a period through March 18, which showed Rosenberg spending less than $13,000 and Diny spending nearly $60,000. But that spending skyrocketed in the weeks leading up to the election, with totals likely reaching upwards of $330,000. Of that, more than $190,000 was spent on campaign messages supporting Rosenberg. More than $90,000 was spent to promote Diny, according to wispolitics.com. The race is nonpartisan.

Wausau voters came out in droves to cast ballots on a day in which the city was under a winter storm warning, with heavy snow and slippery travel conditions. Voter turnout in Marathon County was nearly 40 percent, up from about 32 percent two years ago when the most recent City Council was elected.

Residents bemoaned the flurry of smear ads that filled mailboxes and appeared on internet screens, someof which were funded by dark money groups or outside entities that can easily skirt campaign finance reporting regulations. Both candidates spoke out against the negative ads, but unclear is whether either approved the heavily negative messaging that could have influenced the race.

According to the unofficial tally, Diny received 5,222 votes with Rosenberg receiving 4,798. There were 16 write-in votes. All results are unofficial until certified by the Marathon County Clerk.

Diny released a statement late Tuesday thanking voters for their confidence in him and thanking his opponent for her service.

“I want to thank the voters of Wausau for electing me to be their next mayor and I want to thank Mayor Rosenberg for her years of service to the community,” Diny said. “Thank you also to my supporters and all of the grassroots volunteers who made this possible. I want every Wausonian to know that I will be a mayor for all. I am ready to get to work and help make Wausau an affordable place to live, start a business, and grow a family.”

Rosenberg was first elected mayor in 2020. Mayor serve four-year terms and earn an annual salary of $78,873.60, or around $38 per hour.

To see the full breakdown of election results, visit the Marathon County Elections page at this link.