Did South Dakota voters shift further left in 2026 federal races?

A greater percentage of South Dakota voters voted for federal Democratic candidates in the 2026 general election than in the 2024 general election. 

In the 2024 general election, 72% of South Dakotans voted for Republican Rep. Dusty Johnson in the U.S. House of Representatives, versus 28% for Sheryl Johnson, a Democrat.

In 2026, 36% of voters voted for Democrat Nikki Gronli in the U.S. House of Representatives race and 64% voted for Republican Marty Jackley.

In 2024, 63% of South Dakota voters cast ballots for President Donald Trump, the Republican candidate, and 34% cast ballots for Kamala Harris, the Democratic candidate.

Another federal race saw a smaller margin of Republican victory but did not include a Democratic candidate. The U.S. Senate race between Independent Brian Bengs and U.S. Sen. Mike Rounds, a Republican, saw 61% vote for Rounds and 39% vote for Bengs.