Michigan's 9th congressional district is a United States congressional district located in The Thumb and northern portions of Metro Detroit of the State of Michigan. Counties either wholly or partially located within the district include: Huron, Tuscola, Sanilac, Lapeer, St. Clair, Macomb and Oakland. With a Cook Partisan Voting Index rating of R+18, it is the most Republican district in Michigan.

Huron County is a county in the U.S. state of Michigan. As of the 2020 Census, the population was 31,407. The county seat is Bad Axe. Huron County is at the northern tip of the Thumb, which is a sub region of Mid Michigan. It is a peninsula, bordered by Saginaw Bay to the west and Lake Huron to the north and east, and has over 90 miles (140 km) of shoreline, from White Rock on Lake Huron to Sebewaing on the Saginaw Bay. Huron County's most prominent industry is agriculture, as with most of the other Thumb counties. Huron County enjoys seasonal tourism from large cities such as Detroit, Flint, and Saginaw. Much of the tourism is in the Port Austin and Caseville area.