Coordinates: 42°37′43″N 94°38′42″W / 42.62861°N 94.64500°W / 42.62861; -94.64500 Iowa's 4th congressional district is a congressional district in the U.S. state of Iowa that covers its northwestern part, bordering the states of Minnesota, South Dakota, and Nebraska, and the Missouri River. The district includes Sioux City, Ames, Mason City, Fort Dodge, Boone and Carroll; it is currently represented by Republican Randy Feenstra, who has been in office since 2021. With a Cook Partisan Voting Index rating of R+16, it is the most Republican district in Iowa. From Wikipedia
