Forecasts of the 2026 midterm elections from polls, prediction markets, academic models and the PLSC 2219 class model, updated daily.
Forecasts for this seat as of 2026-10-20. Partisan lean: R+14.6. Margins are Democratic minus Republican.
In this race the main opponent of Republican Mike Rounds is Brian Bengs, an independent. Every margin and chance on this page compares Brian Bengs with Mike Rounds, not a Democrat with a Republican: I+ means Brian Bengs is ahead, and P(D wins) is the chance that Brian Bengs wins.
| Source | Margin | P(D wins) | Sources |
|---|---|---|---|
| Markets | — | 5% | 3 |
| Academic | R+21.8 | 0% | 6 |
| Class model | R+23.9 | 2% | 1 |
“Sources” counts the forecasts in each average. “Not shown” counts forecasts that are in the average but withheld individually.
The last four months.
The last five regular elections for this seat (2020, 2014 and earlier). Results from the MIT Election Data and Science Lab.
| Year | Margin | Winner |
|---|---|---|
| 2020 | R+31.5 | Mike Rounds |
| 2014 | R+26.1 | Mike Rounds |
| 2008 | D+25 | Tim Johnson |
| 2002 | D+0.2 | Tim Johnson |
| 1996 | D+2.6 | Tim Johnson |