Iowa: Ernst's Senate Seat Is a Real Fight

The biggest open race of the night was Iowa's Senate contest. Republican Rep. Ashley Hinson led challenger Jim Carlin, a former state senator, for the GOP nomination to replace outgoing Sen. Joni Ernst, according to The Hill's live results.

Hinson is the establishment pick. Carlin ran to her right. Iowa's open Senate seat is one the GOP cannot afford to treat lightly — not in a cycle where Democrats will be hunting for any pickup they can find.

On the Democratic side, Iowa voters also selected their nominee. Whoever wins that general election in November will shape the Senate math for the next six years.

Iowa Governor: Feenstra Moves Up

Rep. Randy Feenstra (R) was the frontrunner in the GOP gubernatorial primary to succeed outgoing Gov. Kim Reynolds, according to The Hill. Reynolds is term-limited out.

Feenstra vacating his 4th Congressional District seat creates a second open House race in Iowa. Both the 2nd and 4th Districts are now in play, per The Hill, with no incumbents to protect either seat.

Montana: Zinke Retires, Democrats Smell Blood

Rep. Ryan Zinke (R) is retiring from Montana's 1st Congressional District. Democrats view the 1st District as a pickup opportunity, according to The Hill. Montana is a state where Republicans have dominated federal races, but an open seat with no incumbent changes the dynamics.

Montana's Senate seat is held by Republican Sen. Steve Daines, who is running for reelection. Former U.S. District Attorney Kurt Alme, a Republican, was among the candidates vying for the GOP primary nomination to challenge in down-ballot races, per The Hill.

California: 30 Days of Counting Ahead

June 2 primaries wrapped across California, Iowa, Montana, New Jersey, New Mexico, and South Dakota. California's count will drag on for weeks, per state law, which gives county officials up to 30 days to complete the official canvass, according to the NY Post.

California's governor's race featured a crowded field of Democrats and Republicans competing under the state's top-two primary system, where the top two vote-getters advance to November regardless of party. That means two Democrats could face each other in the general — or a Republican could sneak into second place in a fragmented field, according to The Hill's live results coverage.

Gov. Gavin Newsom is term-limited. His seat is genuinely open for the first time in years.

Nancy Pelosi's old 12th Congressional District is also on the ballot as one of six open House seats in California this cycle, per The Hill. California has 52 House districts. Republicans need every seat they can get.

California accepts mail ballots postmarked by Election Day and received later — final results in close races may not be known for days or weeks.

New Jersey and New Mexico: Less Drama, Still Matters

Sen. Cory Booker (D-NJ) was waiting to find out his Republican opponent Tuesday night, according to The Hill. A handful of GOP candidates competed for the right to challenge Booker in November. New Jersey is tough terrain for Republicans.

In New Mexico, Sen. Ben Ray Luján (D) faces reelection. No Republican filed to run against him in the primary, per The Hill.

On the governor's side, former Interior Secretary Deb Haaland was leading Sam Bregman, a district attorney, on the Democratic side, according to The Hill.

South Dakota: Still Unresolved

Gov. Larry Rhoden (R) faced a tough primary in South Dakota after ascending to the governorship when former Homeland Security Secretary Kristi Noem vacated the seat. Sen. Mike Rounds (R) was running for a third term and was expected to advance, per The Hill.

Rep. Dusty Johnson opted to run for governor rather than defend his House seat, creating another open congressional race.

The Cascade of Open Seats

National coverage treated June 2 as largely a California story. California's results won't be known for weeks anyway.

The cascade of open seats — Iowa Senate, Iowa's two House seats, Montana's 1st House District, South Dakota's House seat — creates genuine volatility in races that Republicans need to hold.

Democrats only need to flip a handful of seats. Republicans need to defend everything and pick up gains. The 2026 midterm map just got more complicated than either party anticipated.