Iowa set its November battleground Tuesday night, with voters delivering primary results in races for governor, U.S. Senate, and all four congressional seats—a ballot shaped largely by two retirements that opened the door to the most competitive statewide elections Iowa has seen in years.
For the first time since 2006, Iowa’s governor’s race has no incumbent on the ballot, and US Sen. Joni Ernst’s retirement left Iowa’s U.S. Senate seat open for the first time in over a decade. Both races are expected to be genuine toss-ups in November.
Governor: MAHA beats MAGA in Iowa’s biggest upset of the night
Zach Lahn, a 40-year-old farmer and entrepreneur from Belle Plaine, will be Iowa’s Republican nominee for governor — after defeating Trump-endorsed U.S. Rep. Randy Feenstra in one of the most surprising results of the 2026 primary season anywhere in the country.
With 98% of the expected vote counted Tuesday night, Lahn had 37.8% to Feenstra’s 37% — a margin of less than one percentage point. It was the first time a Trump-endorsed candidate for governor, the House, or the Senate had lost a primary in the 2026 midterms.
“I just called Zach Lahn, said, ‘Hey, you got to carry this torch. We got to keep this state red. We gotta make sure we beat Rob Sand,’” Feenstra told supporters, CNN reported. “The outcome wasn’t what I wanted, but … God’s got some awesome plans.”
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Lahn ran as a champion of the Make America Healthy Again movement, a lane that put him in direct tension with the Trump establishment machine that had lined up behind Feenstra.
Lahn is considerably less well-known statewide than Feenstra and enters the general election with less money and no congressional profile. His opponent will be Democratic state auditor Rob Sand, who entered the race with a record 24,756 petition signatures — including from Republicans and no-party voters — and roughly $10 million in campaign cash.
Cook Political Report has rated the general election a toss-up.
Congress: Two rematches, one open seat to watch
In IA-01, Rep. Mariannette Miller-Meeks won the Republican primary by more than 70 percentage points over David Pautsch. Christina Bohannan won the Democratic nomination with more than 80% of the vote. It will be the third straight general election matchup between the two. Miller-Meeks won their last contest with exactly 50% of the vote.
In IA-02—the open seat left by US Rep. Ashley Hinson’s Senate run—Lindsay James won the Democratic nomination. James is a state representative and Presbyterian minister from Dubuque County. On the Republican side, former state Rep. Joe Mitchell, who had Trump’s endorsement, will take James on in November.
In IA-03, both US Rep. Zach Nunn and Democrat Sarah Trone Garriott, a state senator from Dallas County, ran unopposed and advanced directly to a general election that national Democrats have targeted as a top pickup opportunity.
In IA-04, Chris McGowan, president of the Siouxland Chamber of Commerce, ran unopposed for the Republican nomination in the seat Feenstra vacated. Former state Rep. Dave Dawson won the Democratic nomination for Iowa’s open 4th Congressional District seat Tuesday, the Associated Press has projected.
