There were 29 Republican primaries for the Ohio House of Representatives on March 19, 2024. An incumbent ran in 19 of those primaries. Five incumbents lost in the primaries, the most since at least 2012.

The 2024 elections took place in the context of a conflict within the House Republican caucus over the election of a speaker. After Republicans won a 67-32 margin in the 2022 elections, 22 Republicans joined with all 32 Democrats to elect Jason Stephens (R) speaker over the winner of the Republican caucus’ internal vote, Derek Merrin (R).

The Ohio Republican Party’s central committee voted to censure all 22 House Republicans who voted for Stephens following his election, including four of the five Republican incumbents who lost their primaries.

The 2024 legislative elections had 29 contested Republican primaries, the most in any year since 2018. Nineteen incumbents—more than one-third of those seeking re-election—faced primary challengers compared to 12 in 2018. This was the highest rate at which incumbent Ohio House Republicans faced primary challenges since at least 2012.

In the five election cycles between 2014 and 2022, 13.7% of Ohio House Republicans facing contested primaries lost re-election. The highest rate of incumbent defeats was 16.7% in 2020 and 2016 while the lowest was 8.3% in 2018. In 2024, 26.3% of incumbents facing contested primaries lost re-election—just under twice the average rate for the preceding decade.

Ohio is one of 23 states with a Republican trifecta. A state government trifecta is a term used to describe a single-party government where one political party holds the governor’s office and a majority in both chambers of the state legislature.