Incumbent Bill Foster, a Democrat, faces a primary challenger: Qasim Rashid. Multiple Republicans are competing in the primary: Susan Hathaway-Altman, Jerry Evans and Kent Mercado.
Votes will be counted in contested races after polls close in Illinois at 7 p.m. Central. See statewide election results here. Last minute questions about voting? View our voter guide. Here is one for Chicago residents and one for suburban residents.
