Markussen announce the filing late Tuesday morning.
The former head of the La Crosse Chamber of Commerce launch her bid last week.
Markussen joins La Crosse common council president Martin Gaul, council members Jessica Olson, businessman Chris Stolpa, former radio host Mitch Reynolds and 18-year-old Sam Schneider.
Current Mayor Tim Kabat announced at the start of the month that he would not seek a third term.
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