Wesley Bell (D) defeated Rep. Cori Bush (D) and two other candidates in the Democratic primary for Missouri’s 1st Congressional District on August 6. Bell received 51.2% of the vote and Bush received 45.6%.

The primary election took place against the backdrop of a federal investigation of Bush’s alleged misuse of campaign funds to pay her now-husband, Cortney Merritts, for security services and the Israel-Hamas War. American Israel Public Affairs Committee’s (AIPAC) super PAC, United Democracy Project, spent $8.5 million either against Bush or in support of Bell.

Although Bush is the most recent incumbent to lose a primary this year, she’s not the first. Let’s take a look at the three other incumbents who lost primary elections this year.

The first incumbent to lose a primary this year was Rep. Jerry Carl (R), who lost the Republican primary for Alabama’s 1st Congressional District on March 5. Rep. Barry Moore (R) defeated Carl 51.7% to 48.3% in the only incumbent vs. incumbent U.S. House election this year. The two incumbents ran against each other after the U.S. District Court for the Northern District of Alabama approved new congressional districts, which placed Moore out of Alabama’s 2nd Congressional District and into the 1st Congressional District.

In the June 25 Democratic primary for New York’s 16th Congressional District George Latimer (D) defeated Rep. Jamaal Bowman (D) 54.5% to 45.5%. In a post-primary analysis of the results, Punchbowl News identified criticisms over Bowman’s conduct in office and Latimer’s long history in local elected politics as key factors alongside satellite spending. According to Punchbowl News, the United Democracy Project spent $14 million in this primary election.

In the June 18 Republican primary for Virginia’s 5th Congressional District, John McGuire (R) defeated Rep. Bob Good (R) 50.3% to 49.7%. Following the primary election, Good requested a recount, as state law allows candidates to do so when the margin is within 1% of the total vote. McGuire won the recount by 370 votes. This primary election took place against the backdrop of Good’s support of Florida Gov. Ron DeSantis in the Republican primary for President and his vote to remove former Rep. Kevin McCarthy (R) as House speaker.

Since 2014, Ballotpedia has tracked 41 incumbents who lost re-election in a primary election. That’s an average of 8.2 incumbents per year.

If this year’s number of incumbents who lost re-election in a primary election holds, 2024 would tie with 2014 and 2018 for the fewest incumbents who lost re-election in a primary election in the last 10 years.

The 16 candidates in 2022 who lost re-election in a primary election were the most incumbents who lost re-election in a primary election in the last 10 years. According to Axios, some factors that contributed to the high loss rate that year included incumbents who ran against other incumbents due to apportionment, former President Donald Trump’s endorsement against incumbents who voted to impeach him, and ethics controversies.