The only positions not being challenged are for seats held by incumbent Coroner Tom Clary and Surveyor Scotty Simer. Both are Democrats.
Democrat Sheriff George Underwood, seeking his second term, will face former Alton Police Chief Mike Barton in the August primary election.
On the Republican ticket for sheriff, former Alton Police Chief Kevin Jotz, former Thayer Assistant Police Chief Michael Bunting and current Thayer Police Chief David Bailey will square off in the primary election.
Incumbent Democrat John (Big John) Wrenfrow has been challenged by Democrat Nathan Roberts and Republicans Alonzo Bradwell and Jason Kemper, an Alton School Board member.
Incumbent Republican Edward Casey has been challenged by Democrat Brad Vest, who ran against Casey in 2010.
Incumbent Republican Mike Crawford has been challenged by Democrat Mike Harber, a Thayer alderman.
Incumbent Democrat Charles Alford will face Republican Russell Grooms.