The Democratic ticket is set in South Dakota's gubernatorial race.
Susan Wismer named Susy Blake as her lieutenant governor running mate.
Blake is a former state legislator and nurse. She represented District 13 in Sioux Falls from 2008 to 2012.
"It was an honor to be asked to join Susan for this historic campaign, and now it is my pleasure to join this campaign and stand with Susan to advocate for all of the people of South Dakota," Blake said in a statement.
Wismer won the Democratic gubernatorial nomination in a primary election June 3. The state representative from Britton will campaign against Republican Governor Dennis Daugaard and Independent candidate Michael J. Myers leading up to the November general election.