HarrisDemocratic32.9%5,074TrumpRepublican64.3%9,904OtherAll other candidates2.8%431
R+31.3- Lead
- 4,830
- Total
- 15,409
- vs nation
- R+29.9
modeled Census-place estimatemodeled estimate
Akashicstate senate district
South Dakota 31st State Senate District
Office (updates table and map)
President margin by year
Place winner margin
Boundary by 2024 margin · Precinct returns · VEST · MIT Election Lab
The precinct map shows the 2024 presidential vote; the timeline scrubs the district’s overall result across 1892–2024, on its current boundaries.
President results by year
Modeled candidate-vote estimate on current district boundaries
BidenDemocratic32.8%4,537TrumpRepublican63.3%8,753OtherAll other candidates3.9%538
R+30.5- Lead
- 4,216
- Total
- 13,828
- vs nation
- R+34.9
modeled Census-place estimatemodeled estimate
ClintonDemocratic28.3%3,356TrumpRepublican62.6%7,411OtherAll other candidates9.1%1,075
R+34.2- Lead
- 4,055
- Total
- 11,842
- vs nation
- R+36.3
modeled Census-place estimatemodeled estimate
ObamaDemocratic35.0%3,973RomneyRepublican61.8%7,025OtherAll other candidates3.2%361
R+26.9- Lead
- 3,052
- Total
- 11,359
- vs nation
- R+30.7
modeled Census-place estimatemodeled estimate
ObamaDemocratic40.9%4,932McCainRepublican56.3%6,787OtherAll other candidates2.8%336
R+15.4- Lead
- 1,855
- Total
- 12,055
- vs nation
- R+22.7
modeled Census-place estimatemodeled estimate
KerryDemocratic33.2%3,857BushRepublican64.5%7,489OtherAll other candidates2.3%273
R+31.3- Lead
- 3,632
- Total
- 11,619
- vs nation
- R+28.8
modeled Census-place estimatemodeled estimate
GoreDemocratic29.7%2,797BushRepublican67.3%6,327OtherAll other candidates3.0%282
R+37.5- Lead
- 3,530
- Total
- 9,406
- vs nation
- R+38.0
modeled Census-place estimatemodeled estimate
ClintonDemocratic37.8%3,568DoleRepublican46.9%4,430OtherAll other candidates15.3%1,444
R+9.1- Lead
- 862
- Total
- 9,442
- vs nation
- R+17.7
modeled Census-place estimatemodeled estimate
Key facts
- 2024 presidential margin
- R+31.3MIT Election Lab
- Population
- 25,7682024 5-year
- Population density
- 32 / sq mi2024 5-year · TIGER/Line
- Land area
- 800 sq miTIGER/Line
- Median household income
- $73,3842024 5-year
- White (non-Hispanic)
- 89.0%2024 5-year
- Black
- 0.4%2024 5-year
- Hispanic / Latino
- 3.6%2024 5-year
- Peak Democratic margin
- D+53.9 in 1912MIT Election Lab
- Peak Republican margin
- R+56.8 in 1924MIT Election Lab
- Most similar
- State Senate District 9, MT · twin score 91.3
presidential history
Party record book
South Dakota 31st State Senate District · the strongest Democratic and Republican presidential performances recorded here, measured three ways.
1892–2024 · 20 presidential cycles
Highest vote share
Largest share of the presidential candidate vote cast here.
Democratic
William J. Bryan1896
56.4%
2,905 votes · D+13.5 · modeled estimate
Runner-up · Woodrow Wilson, 1912 · 53.9%
Republican
Ronald Reagan1984
69.4%
5,949 votes · R+39.5 · modeled estimate
Runner-up · Warren G. Harding, 1920 · 68.6%
Most votes
Largest number of votes cast for the party’s presidential nominee here.
Democratic
Kamala Harris2024
5,074votes
32.9% of the vote · R+31.3 · modeled estimate
Runner-up · Barack Obama, 2008 · 4,932 votes
Republican
Donald Trump2024
9,904votes
64.3% of the vote · R+31.3 · modeled estimate
Runner-up · Donald Trump, 2020 · 8,753 votes
Best relative to the U.S.
This Place’s margin against the national margin in the same election — positive when it leaned toward the party more than the country did.
Democratic
Woodrow Wilson1912
+34.4pts D vs U.S.
Place D+53.9 · U.S. D+19.5 · modeled estimate
Runner-up · William J. Bryan, 1896 · +19.6 pts
Republican
Benjamin Harrison1892
+39.6pts R vs U.S.
Place R+38.0 · U.S. D+1.7 · modeled estimate
Runner-up · George W. Bush, 2000 · +38.0 pts
current representation
Current officeholders
RRandy DeibertState Senate · 31
State legislative officeholder from OpenStates nightly current-legislator data.
U.S. House elections · 2 House
Senate and governor results are in the Office selector at the top of this page.
U.S. House
Each row is a county-allocated estimate of U.S. House votes for this district — county returns apportioned onto its boundary, not precinct-counted. “Vote lead” is the estimated local lead here, not necessarily the winner of the full contest.
| Year | Vote lead | Democratic | Republican | Total |
|---|---|---|---|---|
| 2020 | R | 0.0%0 | 100.0%9,917 | 9,917 |
| 2018 | R | 33.7%3,301 | 66.3%6,499 | 9,800 |
The district recorded a Republican presidential margin of R+31.3 in 2024 and R+15.4 in 2008, switching sides at least once in between. About 27,200 residents lived here, with White alone at 90.4% in the 2024 ACS 5-year.
Across the recorded series it reached a Democratic high of 53.9 points in 1912 and a Republican high of 56.8 points in 1924. Between 2020 and 2024 the district moved 0.9 points toward the Republican candidate; the 2024 margin was 31.3 points.
A population of 25,768, a 89% non-Hispanic-white share, and a median household income of $73,384 describe the district. The district's voting pattern over the last decade is most similar to that of State Senate District 9 and State Senate District 28.
Political twins — state-senate districts
The state-senate districts whose fingerprint — 2000–2024 trajectory, demographics, ancestry, religion — sits closest to this one, and why.
State Senate District 9
Montana
91.3twin score
population scale2012–2016 trajectoryelasticity
State Senate District 28
Montana
91.2twin score
2012–2020 trajectorypopulation scale≠ % unaffiliated
State Senate District 33
South Dakota
91.1twin score
2012–2020 trajectorypopulation scale≠ French ancestry
Twin score (0–100) = weighted cosine between tier-standardized fingerprints: presidential margins 2000–2024 with 12-yr trend and elasticity, ACS income, age, education, population and race, top reported ancestries, and religious adherence — chips name the closest-shared dimensions and the widest gap. Re-weight the groups in the twins explorer.
District research tools
Open the source-auditable district brief for electoral baseline, electorate, current-cycle coverage, geography, official dates, and methodology. Open campaign intelligence report → · Browse all comparisons →
Cite this page
All citations released under CC BY 4.0. Attribution: Akashic Intelligence.
South Dakota 31st State Senate District. Akashic. https://akashic.app/sld-upper/46031/. Accessed May 20, 2026. License: CC BY 4.0.
License: CC BY 4.0
South Dakota at the ballot boxAll elections →
Places within South Dakota 31st State Senate District
counties it covers1
Frequently asked questions
How did South Dakota 31st State Senate District vote in 2024?
In 2024, South Dakota 31st State Senate District voted Republican by 31.3 points (R+31.3), carried by the Republican candidate. Out of 15,409 votes cast, 5,074 went Democratic and 9,904 went Republican.
When did South Dakota 31st State Senate District last vote Democratic?
The most recent presidential election in which South Dakota 31st State Senate District voted Democratic was 1916.
How many people live in South Dakota 31st State Senate District?
South Dakota 31st State Senate District has a population of 25,768 according to the 2024 American Community Survey 5-year estimates from the US Census Bureau.
What is the median household income in South Dakota 31st State Senate District?
Median household income in South Dakota 31st State Senate District is $73,384 — below the national median of $80,734. The South Dakota state median is $75,081.
What is the political history of South Dakota 31st State Senate District?
Akashic tracks 38 presidential elections in South Dakota 31st State Senate District from 1876 to 2024. Of those, 3 went Democratic and 31 went Republican.