MILWAUKEE (AP) -- A Democratic primary in southwestern Wisconsin features two candidates running on their legislative experience and two political newcomers running on their lack of it.

The Democrats are state Reps. Mark Pocan and Kelda Helen Roys, attorney Matt Silverman and businessman Dennis Hall. The winner Tuesday takes on Republican Chad Lee in November for the right to succeed U.S. Rep. Tammy Baldwin.

In the state's other congressional primary, Republican U.S. Rep. Tom Petri faces tea party challenger Lauren Stephens. Petri has served in Congress for more than 30 years. The 6th Congressional District covers Fond du Lac and surrounding areas.

The competition in the 2nd District resulted from Baldwin's decision to run for the U.S. Senate seat being vacated by Herb Kohl.