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

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

In Ohio's 12th District Republican primary, David Taylor is projected to win, according to ABC News. With more than 90 percent of the expected vote reporting, Taylor has 25 percent of the vote, putting just ahead of Tim O’Hara (21 percent) and Larry Kidd (19 percent) in a crowded 11-candidate contest. Considering this is solidly red turf, Taylor is all but certain to be the next representative from this suburban-exurban Cincinnati area seat.

—Geoffrey Skelley, 538

With 68 percent of the expected vote reporting, Bost leads Bailey 53 percent to 47 percent in the Republican primary in Illinois's 12th District. But Bost looks to be on pace for a potentially narrower win — and perhaps could even lose. After the 2020 Census, Illinois Democrats drew a gerrymander that packed more Republican-leaning turf into Bost's 12th District in southern Illinois, which he had represented since 2015. About half of the new-look version of the seat had been in Bost's old district, but much of the eastern part of the seat was new to him. Meanwhile, Bailey's old state Senate seat made up a large chunk of that eastern section, giving him a geographical base of support for this primary despite facing the incumbent Bost.

As things stand, Bost is winning about 70 percent of the vote so far in the area he represented prior to the 2022 election, while Bailey is winning 73 percent in the counties that were in his old state Senate seat. The two are running about even in the remaining turf. The good news for Bost is that more of the primary vote will likely come from his neck of the woods. But the good news for Bailey is that more outstanding votes are likely left to be counted in his area of the district. A back of the envelope calculation based on each candidate's showing so far would put Bost up about 51 percent to 49 percent by the time all is said and done, but that is too close to call.

—Geoffrey Skelley, 538

I mentioned earlier that Merrin had been involved in a speaker fight in Ohio that he lost when another candidate, Stephens, won the backing of Democrats to hold a more moderate speakership. Twenty-two Republicans in the state House joined in voting for Stephens, including Stephens himself, and were dubbed the Blue 22. They were censured by the state party. Of those running again, 12 face primary challengers. By our count, 8 of the Blue 22 running for reelection are currently ahead and 4 are running behind their challengers, according to the Ohio Secretary of State. Stephens is running unopposed, but that could spell doom for his speakership.

—Monica Potts, 538