These elections will be conducted using redistricted boundaries, which didn't change much from those in use over the past decade.
District 1, where the polls close at 7:00 PM ET, will be an early race to watch in terms of how the night is going to play out for the parties. Democrat Frank Mrvan is seeking a 2nd term.
The other districts are safe for the incumbent party. Districts 2 and 9 will see the election of new representatives, most likely Republican. The District 2 seat is currently vacant, after the death of Republican Jackie Walorski in August. There is a separate special election November 8 to fill the seat during the lame-duck session.