Illinois and Ohio primaries 2024: Trump-backed Senate candidate prevails in Ohio primary

538 tracked key House and Senate races, including a California special election.

November’s presidential matchup may be set, but Democrats and Republicans still need to decide who will run in hundreds of downballot races (e.g., for Senate and House) this fall. A batch of these contests were decided on Tuesday, March 19.

Tuesday was primary day in Ohio and Illinois, and in the biggest contest of the day, Republicans chose former President Donald Trump's endorsee Bernie Moreno as their candidate in Ohio’s U.S. Senate race. It was a good night for other Trump endorsees too, as Derek Merrin prevailed in the GOP primary for Ohio's 9th Congressional District, while incumbent Mike Bost is leading his challenger in Illinois's 12th District, as of early Wednesday morning. Plus, a special election in California could have immediate implications for House Republicans’ razor-thin majority.

538 reporters and contributors broke down the election results as they came in with live updates, analysis and commentary. Read our full live blog below.

Two outstanding races

Finally, two of our key races aren’t likely to be settled tonight. Here’s where things stand as of midnight Eastern:

- Illinois’s 12th District GOP primary is on a knife’s edge: Republican Rep. Mike Bost narrowly leads former state Sen. Darren Bailey 52 percent to 48 percent with 75 percent of the expected vote reporting. This makes it our lone unprojected race of note in Illinois or Ohio.

- Out west, the special election in California’s 20th District to fill the vacancy left by former House Speaker Kevin McCarthy’s resignation looks to be headed for a May 21 runoff. With 79 percent of the expected vote reporting, Republican state Assemblymember Vince Fong leads with 40 percent, followed by 26 percent for fellow Republican Mike Boudreaux, the Tulare County sheriff. But Democrat Marisa Wood has 24 percent, so she could conceivably surpass Boudreaux for second place. Still, no candidate looks on course to win a majority, making a second vote two months from now very likely.

—Geoffrey Skelley, 538

And the winners are ...

It’s midnight Eastern, and all but one of our key races have been projected in Ohio and Illinois. Here’s a recap of where things stand in those races:

- Former President Donald Trump once again flexed his muscles in the Ohio Senate race, elevating former car salesman Bernie Moreno from a 2022 also-ran to the GOP nominee in one of the two top Senate races on the map, beating an uber-rich state senator and a two-time statewide officeholder in the process. But Moreno’s toughest path lies ahead, against well-funded incumbent Democratic Sen. Sherrod Brown. With 96 percent of the expected vote reporting, Moreno leads with 51 percent of the vote over state Sen. Matt Dolan’s 33 percent and Ohio Secretary of State Frank LaRose’s 17 percent.

- In Ohio's 9th District, the conservative backed by Trump and House Speaker Mike Johnson, state Rep. Derek Merrin, is projected to win, and ready to take on Democratic Rep. Marcy Kaptur in what could be a tough general election race. With 80 percent of the expected vote reporting, Merrin has won 52 percent of the vote, 18 percentage points ahead of his nearest competition.

- In Ohio’s 13th District, another potentially competitive Democratic-held seat, former state Sen. Kevin Coughlin advanced out of the GOP primary rather easily and will take on Democratic Rep. Emilia Sykes in November. With 80 percent of the expected vote in, Coughlin leads with 65 percent of the vote so far over businessman Chris Banweg’s 28 percent and Richard Morckel’s 7 percent.

- The Republican Main Street Partnership notched a win against its rivals in the House Freedom Caucus in Ohio’s 6th District, where state Sen. Michael Rulli is projected to beat state Rep. Reggie Stoltzfus. Rulli currently leads by 9 points with 83 percent of the expected vote reporting in the regular primary, and by 8 points with 82 percent of the expected vote in the special election. Rulli will face a nominal challenge from Democrat Michael Kripchak on June 11 in the special election to replace Rep. Bill Johnson.

- In another safe GOP seat, Ohio’s 2nd District Republican primary went for business owner David Taylor, who won a crowded race that was tantamount to election in November. With 95 percent of the expected vote reporting, Taylor leads with 25 percent of the expected vote over 10 other challengers.

- Despite several challengers lining up to replace Democratic Rep. Danny Davis, the long-time incumbent is likely to hold onto his seat in Illinois’s 7th District. With 76 percent of the expected vote in, Davis leads with 53 percent of the vote so far. In second is Chicago City Treasurer Melissa Conyears-Ervin with 22 percent, followed by community organizer Kina Collins with 18 percent. Collins was seen as Davis’s primary competition tonight, and her underwhelming performance was part of a tough night for progressives in Chicago.

—Jacob Rubashkin, Inside Elections; Geoffrey Skelley and Monica Potts, 538

Chicago races are a mixed bag for progressives

In downballot races in Chicago tonight, it looks to be something of a mixed result for the progressive movement. On the legislative level, moderate challengers failed to oust more progressive-leaning state legislative incumbents across the Chicago area. The more progressive candidate also has been projected to win state Senate District 20, according to the Associated Press. However, as I mentioned earlier, marquee progressive items look to be losing: Both the “Bring Chicago Home” referendum and Cook County State’s Attorney Democratic primary show progressives behind.

So despite the mayor’s unpopularity, and some indications in polls that the progressive movement might be on the wane in the city, there’s a bit of good news for both sides of the Democratic divide tonight.

—Mary Radcliffe, 538

It was a tough night for Republican women and a mostly good night for Democratic women

Only three of the eight Republican women we were tracking won their primary races: Two of them were uncontested and are in deep blue districts, where they are unlikely to win in November. One, Miller in Illinois's 15th, is the incumbent. On the flip side, 13 of the 17 Democratic women we were tracking won their races, many of them incumbents likely to hold their seats in November.

Women have record representation in Congress now, but of course still lack parity. But in this election, issues that women care about, namely abortion and reproductive rights, are poised to make a difference. Democratic voters could be motivated to turn out to protect abortion rights at the national level, and Democratic candidates are likely to run on the issue going forward.

—Monica Potts, 538