Lead: Illinois’ March 17, 2026 primary closed at 7:00 p.m. local time, and vote-counting through the evening produced a string of key projections: Lt. Gov. Juliana Stratton led and was later projected to win the Democratic U.S. Senate primary, Daniel Biss was projected the winner in the crowded 9th Congressional District, and Republican Darren Bailey was projected to win his party’s gubernatorial primary. Several other competitive congressional primaries produced clear front-runners or projected winners, while officials reported strong turnout and long early-voting lines in parts of Chicago. These results set the stage for high-profile November rematches and open-seat contests across the state.
Key takeaways
- Daniel Biss was projected the winner of the Democratic primary in Illinois’ 9th Congressional District (projection announced at 9:38 p.m.). The seat opened with Rep. Jan Schakowsky’s retirement after nearly three decades.
- Juliana Stratton was projected to win the Democratic primary for U.S. Senate (projection at 9:30 p.m.), leading with roughly 39.4% of the vote in a 10-candidate field with major rivals Raja Krishnamoorthi and Robin Kelly trailing.
- Don Tracy was projected to win the Republican U.S. Senate primary (projection announced at 8:41 p.m.), setting up a likely November matchup against the Democratic nominee.
- Darren Bailey was projected to win the GOP gubernatorial primary with about 49.6% of the vote when 40% of ballots were reported, positioning a rematch with incumbent Gov. JB Pritzker in November.
- Melissa Bean was projected to win the 8th Congressional District Democratic primary (9:18 p.m.), and Donna Miller was projected to win the 2nd District Democratic primary (8:24 p.m.).
- Incumbents held in several races: Mike Quigley was projected to win the 5th District Democratic primary and Sean Casten was projected to win the 6th District Democratic primary (Casten reported with 73.4% in one update).
- Toni Preckwinkle led decisively for Cook County Board President and Ald. Brendan Reilly conceded after returns showed Preckwinkle with roughly 68% of the vote with 79% counted.
- Chicago reported strong participation: early and mail-in ballots pushed city turnout into the high-teens to low-20s percentage range by mid- to late-day, with recorded 5 p.m. Chicago turnout at 21.84% (339,427 ballots counted).
Background
Illinois’ 2026 primary arrived with several long-held seats open after retirements. U.S. Sen. Dick Durbin’s seat drew a crowded Democratic contest after nearly 30 years in office, while Rep. Jan Schakowsky and Rep. Danny Davis both left their House seats open, producing large candidate fields in the 9th and 7th districts respectively. Those vacancies, plus competitive intra-party battles, attracted both local and out-of-state donor attention and a broad array of candidates spanning multiple generations and ideological wings.
Fundraising patterns shaped expectations: campaign finance reports showed Raja Krishnamoorthi outraised many rivals with more than $30 million for his Senate bid, while Lt. Gov. Juliana Stratton’s campaign benefited from more than $4 million raised for her and substantial outside spending tied to an Illinois Future PAC. In the 9th District, outside small-dollar fundraising fueled challengers—Kat Abughazaleh raised more than $3.3 million largely from small donors, Laura Fine raised over $2.5 million, and Daniel Biss raised roughly $2.3 million, much of it from in-state donors.
Turnout and election administration also framed the day: Illinois does not use runoffs for primary nominations, meaning plurality winners—especially in very crowded contests—can advance with relatively low vote shares. Cook County and Chicago officials reported record early-voting levels and deployed new tools such as an Election Lens system to monitor ballots and polling-place conditions in real time.
Main event
Polls closed statewide at 7:00 p.m., though voters in line at that time were allowed to cast ballots. Early evening reporting showed tight and shifting margins in several marquee races. Within minutes of polls closing, Stratton and Krishnamoorthi traded narrow leads in the Democratic Senate contest; as more returns arrived, Stratton extended her advantage and was projected the winner later in the night.
The 9th Congressional District, one of the most closely watched races, featured 15 Democrats competing to replace Jan Schakowsky. Daniel Biss emerged as the projected nominee after a night of changing tallies: he led early, saw challengers surge in parts of the count, and then was called the winner as final returns and model analysis favored his plurality. Kat Abughazaleh and Laura Fine finished in competitive positions during the count, reflecting intense small-dollar and outside funding flows.
On the Republican side, Don Tracy was projected to win the GOP Senate primary and Darren Bailey was projected to capture the GOP gubernatorial nomination, setting an expected November rematch with Gov. JB Pritzker, who was unopposed in the Democratic primary. Other projected winners included Melissa Bean in the 8th District and Donna Miller in the 2nd District, while several incumbents—Mike Quigley, Sean Casten and Brad Schneider—were projected to hold their nominations.
Analysis & implications
Stratton’s projected primary win in the Senate race signals the potency of institutional support and outside spending in statewide contests. Gov. JB Pritzker’s backing—both direct and through affiliated PAC spending—appears to have helped consolidate moderate Democratic support around Stratton, while Krishnamoorthi’s deep fundraising allowed him to stay competitive through heavy advertising. The outcome will matter less for the general election tilt in Illinois, where Democrats remain favored, and more for intra-party messaging and staffing ahead of the fall campaign.
The 9th District result underscores how crowded primaries can produce winners with modest pluralities. With 15 candidates on the ballot, vote splitting and small-dollar national donations can elevate nontraditional candidates; Biss’s victory shows the advantage of a core base and in-state donor network versus large out-of-state small-dollar fundraising, although late-count dynamics could have changed the result. For November, the Democratic nominee inherits a district that has voted Democratic for decades, but the primary’s narrow margins reveal divisions candidates will need to unify ahead of the general election.
Republican victories in the Senate and gubernatorial primaries (Tracy, Bailey) produce conventional choices for the fall: both nominees are positioned to contrast with Democratic incumbents or favorites on issues like spending and border policy. In the governor’s case, a Bailey-Pritzker rematch will likely refocus national attention on Illinois and rebroadcast the policy differences that defined the 2022 race, including economic messaging and cultural flashpoints.
Comparison & data
| Race | Candidate (status) | Reported share | Percent counted (as reported) |
|---|---|---|---|
| U.S. Senate (D) | Juliana Stratton (projected) | 39.4% | ~80% |
| U.S. Senate (R) | Don Tracy (projected) | — (projection) | — |
| Governor (R) | Darren Bailey (projected) | 49.6% | 40% |
| 9th CD (D) | Daniel Biss (projected) | — (projection) | — |
| 2nd CD (D) | Donna Miller (projected) | 41.3% (early) | 71% |
| 6th CD (D) | Sean Casten (projected) | 73.4% | 39% |
These figures reflect snapshot reporting and network projections during the evening; late-arriving precincts and outstanding mail-in ballots can alter final percentages. The table highlights both races decided by projection and those with only partial counts at the times listed.
Reactions & quotes
Campaigns and observers framed returns through lens of turnout and organizational strength. After conceding in the Cook County board race, Brendan Reilly emphasized continued civic engagement despite defeat, and Toni Preckwinkle’s campaign underscored experience as a deciding factor.
“My commitment to this city and this county is completely unbroken,”
Brendan Reilly, Alderman (concession statement)
In the 7th District voting snafu involving candidate La Shawn Ford, Ford stressed voters deserve certainty and regular ballots rather than provisional ones when eligible. Election officials later resolved the issue and allowed him to cast a regular ballot.
“I was not going to accept a provisional ballot when I knew I was entitled to cast a regular ballot that would be counted without question,”
La Shawn Ford, 7th District candidate
Political scientists warned that plurality winners from crowded fields can introduce legitimacy concerns and unpredictability for November. Professor Stephen Maynard Caliendo noted plurality outcomes are likely in multi-candidate primaries and that could produce unexpected nominees.
“When you have this many candidates, somebody’s going to win with a pretty low percentage of the overall vote,”
Stephen Maynard Caliendo, political scientist
Unconfirmed
- Whether all outstanding mail-in and provisional ballots will materially change any projected winners remains a possibility until official counts are certified; late tallies could narrow margins in close contests.
- Claims about the geographic origin breakdown of small-dollar donations in certain campaigns (outside vs. in-state) come from campaign finance summaries but may require further audit for final attribution.
Bottom line
The March 17 primary reshaped several Illinois contests: a competitive Democratic Senate primary produced a projected winner in Juliana Stratton, crowded House primaries delivered plurality nominees in open seats, and Republican primaries produced standard-bearers who will compete in the fall. High early and election-day turnout made the results more consequential and less predictable than a routine midterm primary.
Looking ahead, certified counts over the next days will finalize close margins and determine whether any last-minute changes occur. For November, the outcomes narrow candidate fields for general-election matchups that will test whether elevated spring turnout translates into sustained engagement for the fall campaigns.
Sources
- CBS News live updates (media: live election reporting)
- Illinois Board of Elections (state election authority)
- Cook County Clerk / Board of Elections (local election administration)
- Capitol News Illinois (local political reporting)
- AdImpact (advertising tracking and analysis)