The 2008 United States Senate election in South Dakota was held on November 4, 2008. Primary elections were held on June 3, 2008. Incumbent Democratic U.S. Senator Tim Johnson won re-election to a third term.
One of the other reasons why Johnson is popular is earmarks. Recent examples include $248,000 for the Dahl Arts Center in Rapid City, $11 million for Ellsworth Air Base, $400,000 for Rosebud Sioux Reservation, and $37 million for Mni Wiconi Rural Water System. Dykstra opposed earmarks, leading U.S. Senator Tom Coburn to campaign with him.
In August, Johnson visited 20 cities across the state. With nine reservations in the state, American Indians account for 10% of electorate. In 2002, Johnson carried 94% of the Oglala Sioux, the state’s biggest tribe.