South Dakota Senate

99%

GOP

1%Ind

Solid R

— No change since last week

Range of Outcomes

Median outcome: R+15.080% of simulations: R+21.8 to R+8.2

How We Got This

Partisan Lean

how the seat votes compared with the nation

R+26.2

Fundamentals

candidates, fundraising, experts

R+1.8

National Environment

current political climate

I+3.4

Polls

recent state and district polling

I+9.6

Forecasted margin

R+15.0

What Changes the Forecast

The polls and fundamentals are picking a fight. More polling should tell us which one to believe.

Polls

Race polls
Pollster	Date	Margin	Population
Emerson College KELO-TV	Oct 21, 2026	R+8	LV
Quantus Insights	Oct 19, 2026	R+22	LV
Public Opinion Strategies Mike RoundsRepublican	Oct 16, 2026	R+17	LV
Concord Public Opinion Partners Education Reform Now AdvocacyDemocratic	Oct 8, 2026	I+1	LV
Zenith Research Brian Bengs	Sep 27, 2026	R+6	LV

Forecast Over Time

Ind (purple) and GOP (red) win probability over time.

Ind 1%

GOP 99%

Race Details

Expert ratings

Cook Solid R Inside Elections Solid R Sabato Safe R

PVI

R+29 This is a safe Republican state.

Candidates

Independent Brian Bengs

Republican Mike Rounds (inc.)