Rep. Randy Feenstra was seen as the GOP favorite for Iowa governor. But NBC News analysis of election data from 2026 and 2020 shows how Zach Lahn exposed a weakness in his district.

NBC News hasn’t projected the result. Rob Sand was unopposed in his party primary ahead of a general election that’s expected to be competitive.

Zach Lahn won the Republican primary for Iowa governor over U.S. Rep. Randy Feenstra, who was endorsed by the president.