Marion Michael Rounds is an American businessman and politician serving as the junior United States senator from South Dakota since 2015. A member of the Republican Party, he served as the 31st governor of South Dakota from 2003 to 2011.

The governor of South Dakota is the head of government of South Dakota. The governor is elected to a four-year term in even years when there is no presidential election. The current governor is Kristi Noem, a member of the Republican Party who took office on January 5, 2019.