South Dakota’s at-large congressional district has long favored Republican candidates, reflected in the district’s strong partisan lean and the party’s consistent double-digit margins in recent House races. With incumbent Dusty Johnson opting not to seek re-election and instead pursuing the governorship, the June 2 Republican primary produced Marty Jackley as nominee, a former attorney general with statewide name recognition. Democratic nominee Nikki Gronli faces structural headwinds in a state where Republican registration and turnout advantages remain pronounced. Trader consensus at 93.5% for the Republican nominee incorporates these fundamentals while leaving modest room for late-cycle developments such as an unexpected national political shift or candidate-specific events that could alter general-election dynamics before November 3.