South Dakota 2026 SENATE FORECAST

2026 South Dakota Senate Forecast:

Proprietary forecast for South Dakota's Senate election between Democrat Julian Beaudion and Republican Mike Rounds. This page will update with a daily set of 100,000 new simulations as race fundamentals change in order to produce race odds, projected margin, and forecasted vote share.

The 2026 South Dakota Senate election features Democrat Julian Beaudion and Republican Mike Rounds. Incumbent senator Mike Rounds is seeking reelection to a third term, having served in the US Senate since 2015. In 2024, Donald Trump won South Dakota by 29.2%, and Republicans are expected to easily retain the state's Senate seat in 2026. The race will test whether the incumbent party can hold its existing Senate coalition as national conditions shift during the midterm cycle.