South Dakota's Republican Governor Larry Rhoden has won the state's first-ever gubernatorial primary runoff, defeating businessman and cryptocurrency advocate Toby Doeden to secure the party's nomination. The runoff was triggered because neither candidate cleared the 35% threshold required to win the primary outright, a historic first for South Dakota's electoral process. Rhoden's win settles the Republican contest ahead of the November general election, in which he will seek a full term after taking over the governorship.

Doeden ran as a political outsider, building his campaign heavily around cryptocurrency advocacy and positioning himself against the establishment incumbent, but could not overturn Rhoden's lead in the runoff vote. Rhoden will now face Democrat Dan Ahlers, a former state senator, in November. Given South Dakota's long-standing pattern of electing Republicans to statewide office, Rhoden enters the general election as the clear favourite.