- Today
- Holidays
- Birthdays
- Reminders
- Cities
- Atlanta
- Austin
- Baltimore
- Berwyn
- Beverly Hills
- Birmingham
- Boston
- Brooklyn
- Buffalo
- Charlotte
- Chicago
- Cincinnati
- Cleveland
- Columbus
- Dallas
- Denver
- Detroit
- Fort Worth
- Houston
- Indianapolis
- Knoxville
- Las Vegas
- Los Angeles
- Louisville
- Madison
- Memphis
- Miami
- Milwaukee
- Minneapolis
- Nashville
- New Orleans
- New York
- Omaha
- Orlando
- Philadelphia
- Phoenix
- Pittsburgh
- Portland
- Raleigh
- Richmond
- Rutherford
- Sacramento
- Salt Lake City
- San Antonio
- San Diego
- San Francisco
- San Jose
- Seattle
- Tampa
- Tucson
- Washington
DeKalb Today
By the People, for the People
Key Counties to Watch in Illinois Democratic Senate Primary
The race to replace retiring Senator Richard Durbin features a diverse field of candidates vying for votes across the state.
Mar. 18, 2026 at 12:07am
Got story updates? Submit your updates here. ›
The Illinois Democratic primary for the U.S. Senate seat being vacated by the retiring Richard Durbin features a competitive race between three candidates - Lt. Gov. Juliana Stratton, Rep. Robin Kelly, and Rep. Raja Krishnamoorthi. While the Chicago area and its surrounding suburbs make up the majority of the Democratic primary electorate, there are several key counties outside of Cook County that could provide early insights into voter preferences.
Why it matters
The outcome of this primary will have significant implications for the balance of power in the U.S. Senate, as Illinois is a reliably Democratic state in general elections. The geographic and demographic divides within the Democratic electorate in Illinois will be on full display, offering clues about the direction of the party nationally.
The details
Cook County, home to Chicago, will be crucial, as it typically accounts for around 60% of the Democratic primary vote, with Chicago itself making up 40%. The diversity within Cook County means voting patterns in majority-Black, majority-white, and majority-Hispanic neighborhoods will be closely watched. The five "collar counties" surrounding Cook are also expected to favor Rep. Krishnamoorthi, who represents parts of those areas. Downstate Illinois, particularly the Metro East region near St. Louis, as well as university towns like Champaign and DeKalb, could provide insights into the progressive vs. moderate divide within the party.
- Polls close at 8 p.m. Eastern on Tuesday, March 18, 2026.
- Chicago is expected to begin reporting citywide results shortly after polls close, but more detailed breakdowns may not be available until after midnight.
- Suburban Cook County is expected to report live results for the entire area on Tuesday night, but further breakdowns will not be available for days.
- Precinct-level results from St. Clair, Madison, Champaign, and DeKalb counties are expected to start coming in shortly after polls close.
The players
Lt. Gov. Juliana Stratton
A Chicago native who is seen as the more progressive candidate in the race.
Rep. Robin Kelly
A U.S. Representative whose district includes parts of Chicago's South Side.
Rep. Raja Krishnamoorthi
A U.S. Representative who is expected to perform well in the predominantly white, wealthy suburban areas surrounding Cook County.
Sen. Richard J. Durbin
The retiring U.S. Senator whose open seat is being contested in this primary.
Gov. JB Pritzker
The current Democratic governor of Illinois, who won the 2018 primary in a landslide.
What’s next
Election results will start coming in shortly after polls close at 8 p.m. Eastern on Tuesday, March 18, 2026. More detailed breakdowns by county and precinct are expected to trickle in over the following hours and days.
The takeaway
This primary election will showcase the geographic and demographic divides within the Illinois Democratic electorate, providing insights into the party's direction nationally as it seeks to hold onto this Senate seat in the general election.
