With less than five weeks until Election Day, redistricting and changing political conditions have reshaped several House contests, with Republicans occupying most spots on CQ Roll Call’s latest list of vulnerable incumbents.

California Republican Rep. James Gallagher tops the list after winning a June special election under the district's old boundaries, only to face significantly different lines in November that favor Democrats. Republican-turned-independent Rep. Kevin Kiley, also of California, ranks second.

The list was compiled by CQ Roll Call after consultations with party insiders and election analysts, along with reviews of past election results, campaign finance reports, and outside spending. It covers only races involving incumbent members and does not include open seats or contests between two sitting representatives.

Gallagher won 62% of the vote in June while running under the previous boundaries. The new district removes Republican-leaning communities around Yuba City and Redding while adding heavily Democratic areas around Santa Rosa and Healdsburg. Democrat Mike McGuire, a former president pro tempore of the California Senate who finished third in the special election, is expected to challenge Gallagher again.

Kiley faces a different challenge after leaving the Republican Party and running as an independent in a redrawn Sacramento-area district. His Democratic opponent is Richard Pan, a pediatrician and former state senator. Kiley continues to caucus with Republicans in the House and has criticized Speaker Mike Johnson while also seeking to distinguish himself from the party's MAGA wing.

Two Democrats whose districts became more Republican through redistricting also appear near the top of the list. Florida Rep. Darren Soto faces Republican Dan Green after state Republicans redrew the Central Florida district to create additional opportunities for the GOP. Alabama Rep. Shomari Figures is running against Republican state Rep. Rhett Marques after a new congressional map removed Figures' hometown of Mobile and reduced the district's Black voting population to about 40%.

Republican Rep. Zach Nunn of Iowa is also among the incumbents facing a difficult contest. Nunn is running against Democrat Sarah Trone Garriott, who reported raising $5.3 million through June 30 compared with nearly $5 million for Nunn. Rising fertilizer and diesel costs have become an issue in the state's farm economy, while Nunn recently broke with Republican leaders by supporting a resolution requiring congressional approval to continue the war with Iran.

The list also includes Republican Reps. Thomas Kean Jr. of New Jersey, Ryan Mackenzie of Pennsylvania and Juan Ciscomani of Arizona, along with Republican Rep. Mariannette Miller-Meeks of Iowa and Democratic Rep. Don Davis of North Carolina.

Miller-Meeks is again facing Democrat Christina Bohannan, whom she defeated by 799 votes in 2024. Mackenzie, a freshman from Pennsylvania's Lehigh Valley, faces Democrat Bob Brooks, while Ciscomani is being challenged by Marine Corps veteran JoAnna Mendoza in southern Arizona.

Davis faces Republican Laurie Buckhout after North Carolina lawmakers redrew his district to include more Republican-leaning coastal communities and remove several areas of the state's historic Black Belt. Buckhout, a retired Army colonel, previously lost to Davis in 2024.

One notable change from CQ Roll Call's previous ranking is the removal of Missouri Democrat Emanuel Cleaver II. The Supreme Court recently blocked use of a GOP-drawn map that would have made his Kansas City-area district a Republican target. Cleaver is now running in a safely Democratic district, while Missouri voters are set to decide in November whether to approve the proposed congressional map.

The latest list illustrates how redistricting has altered the House battlefield in both directions, with some incumbents gaining safer districts while others are facing substantially different electorates less than five weeks before the midterm elections.