The 4th District covers the most area, but contains the fewest people of Iowa's four congressional districts. Situated in the northwest quadrant of the state, Sioux City, Ames and Mason City are the 4th's major population centers.
Republican Congressman Steve King is seeking his sixth term in the U.S. House. Polling shows Democrat Jim Mowrer trailing King by double digits in the solidly Republican district.
Sources: US Census Bureau, Iowa Secretary of State’s Office
Click on a county to see population and voter registration information. Counties in red have more Republican voters than Democrats or independents, blue have more Democrats and yellow have more independents.
Republican strategist David Kochel and Democratic strategist Jeff Link agree Mowrer's hopes look dim.
"Even strong Democratic candidates fare poorly in this district, with only a few counties that will vote Democratic," writes Kochel over email. "Sioux County is one of the most Republican in the entire country, where Republicans outnumber Democrats almost 9-1."
"Only Cerro Gordo and Webster Counties have real Democratic advantages," writes Link. "Even more urban counties like Story and Woodbury are equally divided between Democrats and Republicans."