Sarah Trone Garriott holds a substantial lead in trader pricing for Iowa’s 3rd Congressional District because the seat has rated as a toss-up or lean Democratic across major forecasters through September 2026, reflecting its narrow margins in the prior two cycles. The Democratic challenger has maintained a fundraising advantage, reporting $5.29 million raised versus incumbent Zach Nunn’s $4.87 million as of late June, and has used those resources for television advertising focused on healthcare access, Medicaid restoration, and opposition to tariff policies affecting farm income. Nunn, a two-term Republican who flipped the district in 2022, faces headwinds in a midterm environment where generic-ballot polling in Iowa has favored Democrats, though his incumbency and endorsements provide a base. Both candidates cleared uncontested primaries in June, setting up a November 3 general election in a district that includes Des Moines and surrounding suburban and rural counties. Early voting begins October 14.