In Iowa’s 1st Congressional District, the margin-of-victory market reflects a rematch between Democratic challenger Christina Bohannan and Republican incumbent Mariannette Miller-Meeks, who prevailed by fewer than 1,000 votes in 2024. Multiple nonpartisan forecasters rate the seat Lean Democratic following shifts in October 2026, consistent with polling averages showing Bohannan ahead by roughly four to eight points and elevated fundraising for both campaigns. An independent candidate on the ballot adds uncertainty by potentially drawing support from either side in a district with narrow historical margins. Trader consensus prices the race as closely contested, with the highest probabilities clustered on modest Democratic margins, underscoring the impact of turnout differentials, late-campaign spending, and performance by statewide Democratic nominees on final vote share.