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.


0

Polls are now closed in Illinois!

Polls have now closed across Illinois, where we'll be monitoring several U.S. House primaries, as well as a closely-watched referendum in Chicago. Rep. Mike Bost is facing a challenge from his right, while Rep. Danny Davis is facing one from his left.

—Cooper Burton, 538


First results in Ohio's 9th

The first votes for Ohio's 9th Congressional District are rolling in, and with 13 percent of the expected vote reporting, Merrin is slightly ahead with 46 percent of the vote, while Riedel is second with 39 percent, and Lankeneau is a distant third (14 percent). As Nathaniel wrote earlier, Merrin was a late addition to the contentious race after audio leaked of Riedel calling Trump "arrogant." And as I wrote earlier, Merrin is no stranger to intra-Republican battles.

—Monica Potts, 538


Ohio Republican and Democratic primary voters have different concerns

As we wait for the first results to trickle in, let's take a look at the issues voters are thinking about in the state. Among likely primary voters in Ohio, Republicans are much more concerned about immigration than Democrats, according to a poll released last week by Emerson College/The Hill/Nexstar. Specifically, given a list of options, 27 percent of voters who said they were very likely to vote in the Republican primary selected "immigration" as the most important issue facing Ohio, while only 2 percent of very likely Democratic primary voters said the same.

Republican primary voters were also more likely than Democratic primary voters to name "the economy (jobs, inflation, taxes)" as the most important issue facing the state, 39 percent to 27 percent. On the flip side, likely Democratic primary voters were more likely than Republicans to select "abortion access," 15 percent to 3 percent, and "threats to democracy," 18 percent to 7 percent.

—Mary Radcliffe, 538


Polls are now closed in Ohio!

Polls have now closed across Ohio. The Buckeye State usually counts its early and mail votes first, so expect to see some large vote dumps right off the bat. A word of caution, though: Early and absentee votes are not necessarily representative of the electorate as a whole. We'll want to wait to get more Election Day votes in before drawing any concrete conclusions.

—Cooper Burton, 538


Senate primary polls usually misfire, but not by this much

As I noted in the opener for our live blog today, the polls in Ohio's Senate race showed a "close race" between Moreno and Dolan, with LaRose in a somewhat distant third. The result, however, is anything but close. With 85 percent of the expected vote reporting, Moreno currently has a lead of 17 points, making for an 18-point miss in our polling average (after you account for some rounding). This is not the largest miss in Senate primary polling history — that honor belongs to surveys of the 2018 Republican primary for a special Senate election in Mississippi — but it is nevertheless very large. An 18-point miss is about 2 times the size of the expected miss of primary polls in historical Senate races (8.2 points).

This miss is notable because it's actually larger than historical expectations. That's the opposite of what we've been seeing with presidential primary polls — which, while they have systematically overestimated support for Trump this cycle, have at least been more accurate than the historical average presidential primary survey. Pollsters will need to do some work to figure out what went wrong.

—G. Elliott Morris, 538