Democratic state Sen. Sarah Trone Garriott is projected to defeat Rep. Zach Nunn (R-Iowa) in Iowa's 3rd Congressional District, according to Decision Desk HQ (DDHQ), handing Democrats a key pickup in a battleground seat that had been held by Republicans for two terms.
Trone Garriott, a Lutheran minister from West Des Moines, built a commanding lead as returns came in Tuesday night. With 88% of the vote counted at 11:22 p.m. EST, DDHQ projected her victory by a 9-point margin.
The district, which includes Des Moines and the fast-growing suburbs of Dallas County, has long been one of Iowa's most competitive. Nunn first won it in 2022 by less than a point, narrowly ousting then-Rep. Cindy Axne (D). He expanded his margin in 2024, beating Democrat Lancon Baccam by nearly 4 points, even as former President Trump carried the district by 4.5 points that same year.
But the political environment shifted dramatically in the 2026 midterms, and national handicappers took notice. In October, the nonpartisan Cook Political Report moved the race from "toss-up" to "lean Democrat," citing the headwinds facing Nunn and Trone Garriott's polling advantage.
Nunn tried to navigate that environment by breaking with the Trump administration on several high-profile issues in the campaign's final stretch. He voted for a war powers resolution that would limit the president's ability to conduct military operations against Iran without congressional approval, and he introduced legislation to block beef imports—a move that put him at odds with the White House on trade policy. Those attempts to project independence came despite Trump's endorsement of Nunn.
Trone Garriott, who has served in the Iowa Senate since 2021, also held a financial edge. She raised nearly $8.1 million through the final weeks of the campaign, compared with Nunn's $6.1 million. Democrats hammered Nunn over his corporate PAC contributions, airing ads that accused him of taking money from Chinese-owned companies. Republicans, meanwhile, targeted Trone Garriott's state Senate record, especially her vote against a ban on gender-affirming care for minors. She pushed back with her own ads, including one in which she said she opposed "letting men in women's locker rooms."
Trone Garriott made healthcare and affordability the centerpiece of her campaign, criticizing Nunn's support for the Republican tax and spending law and warning that its Medicaid provisions would hurt rural Iowa communities.
Her victory is part of a broader Democratic wave in Iowa, where Lindsay James flipped the 2nd District and Democrat Turek flipped a state Senate seat, boosting the party's hopes of a legislative majority. The 3rd District result also adds to the Democrats' midterm sweep, as they prepare to confront the president on multiple fronts.
Trone Garriott's win underscores the vulnerability of Republican incumbents in suburban districts that have trended Democratic in recent cycles. With control of the House at stake, her victory is a significant blow to GOP hopes of holding the chamber.
