A survey by the University of Wisconsin-Madison Elections Research Center shows Senator Bernie Sanders leading in the Democratic primary.
The latest Wisconsin Poll by the University of Wisconsin and the Wisconsin State Journal shows the Vermont senator with 30 percent support among likely primary voters.
All other top candidates including Joe Biden, Elizabeth Warren, Pete Buttigieg, Amy Klobuchar, and Mike Bloomberg are polling between nine and 13 percent. Sanders won the Wisconsin Democratic primary in 2016.