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South Dakota · U.S. Senate in South Dakota · Updated Oct 16, 2026

Mike Rounds

RepublicanIncumbent

Incumbent U.S. senator (2015–present)

2026 race · U.S. Senate in South Dakota

93% chance of winning · race rated Likely R

7%93%

93% chance of winning · race rated Likely R

7%93%
● Brian Bengs● Mike RoundsINC
Full race forecast

Background

Current office
U.S. Senate in South Dakota
Experience
Statewide office or Congress
Past races on file
4 (4 won)

Links: Wikipedia · FEC filings · Candidate list (source)

Electoral history

Earlier races in South Dakota, newest first, matched by name in the results archive.

  1. 2020

    U.S. Senate Nov 3, 2020

    R · 65.7% · 276,232 votes

    Won
  2. 2014

    U.S. Senate Nov 4, 2014

    R · 50.4% · 140,741 votes

    Won
  3. 2006

    Governor Nov 7, 2006

    R · 63.1% · 206,990 votes

    Won
  4. 2002

    Governor Nov 5, 2002

    R · 57.5% · 189,920 votes

    Won

Fundraising

Raised
$3.2M
From individuals
$1.3M
Spent
$2.3M
Cash on hand
$2.7M

Money: FEC, through Jun 30, 2026.

Opponents in 2026