- Lead
- 109,509
- Total
- 164,672
- vs nation
- D+68.0
Ohio 21st State Senate District
President margin by year
Place winner margin
President results by year
Modeled candidate-vote estimate on current district boundaries
- Lead
- 127,826
- Total
- 185,590
- vs nation
- D+64.4
- Lead
- 131,761
- Total
- 191,919
- vs nation
- D+66.6
- Lead
- 150,485
- Total
- 205,745
- vs nation
- D+69.3
- Lead
- 153,504
- Total
- 212,164
- vs nation
- D+65.1
- Lead
- 146,501
- Total
- 210,348
- vs nation
- D+72.1
- Lead
- 115,506
- Total
- 174,752
- vs nation
- D+65.6
- Lead
- 112,139
- Total
- 171,021
- vs nation
- D+57.0
Key facts
- 2024 presidential margin
- D+66.5MIT Election Lab
- Population
- 375,3482024 5-year
- Population density
- 4,147 / sq mi2024 5-year · TIGER/Line
- Land area
- 90.5 sq miTIGER/Line
- Median household income
- $55,6872024 5-year
- White (non-Hispanic)
- 32.0%2024 5-year
- Black
- 58.6%2024 5-year
- Hispanic / Latino
- 2.8%2024 5-year
- Peak Democratic margin
- D+74.9 in 1964MIT Election Lab
- Peak Republican margin
- R+17.8 in 1924MIT Election Lab
- Most similar
- State Senate District 4, PA · twin score 96.9
presidential history
Party record book
Ohio 21st State Senate District · the strongest Democratic and Republican presidential performances recorded here, measured three ways.
1892–2024 (partial returns from 1876) · 38 presidential cycles · 38 with a vote-share denominator · 34 with a national benchmark
Highest vote share
Largest share of the presidential candidate vote cast here.
Democratic
Lyndon B. Johnson1964
87.5%
195,699 votes · D+74.9 · modeled estimate
Runner-up · Barack Obama, 2012 · 86.3%
Republican
Warren G. Harding1920
41.0%
21,311 votes · D+12.9 · modeled estimate
Runner-up · Theodore Roosevelt, 1904 · 40.8%
Most votes
Largest number of votes cast for the party’s presidential nominee here.
Democratic
Lyndon B. Johnson1964
195,699votes
87.5% of the vote · D+74.9 · modeled estimate
Runner-up · Barack Obama, 2008 · 181,975 votes
Republican
Dwight D. Eisenhower1956
50,603votes
29.5% of the vote · D+41.0 · modeled estimate
Runner-up · Richard Nixon, 1972 · 47,181 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
Walter Mondale1984
+73.9pts D vs U.S.
Place D+55.7 · U.S. R+18.2 · modeled estimate
Runner-up · John Kerry, 2004 · +72.1 pts
Republican
Calvin Coolidge1924
−7.4pts R vs U.S.
Place R+17.8 · U.S. R+25.2 · a third-party candidate carried the Place · modeled estimate
Runner-up · Theodore Roosevelt, 1904 · −27.2 pts
Current officeholders
State legislative officeholder from OpenStates nightly current-legislator data.
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 |
|---|---|---|---|---|
| 2024 | D | 66.9%101,337 | 33.1%50,232 | 151,569 |
| 2020 | D | 64.7%112,621 | 35.3%61,485 | 174,106 |
Ohio 21st State Senate District sits in the Industrial Midwest. In 2024 it voted Democratic.
Across the recorded series it reached a Democratic high of 74.9 points in 1964 and a Republican high of 17.8 points in 1924. Between 2020 and 2024 the district moved 2.4 points toward the Republican candidate; the 2024 margin was 66.5 points.
A population of 375,348, a 32% non-Hispanic-white share, and a median household income of $55,687 describe the district. The district's voting pattern over the last decade is most similar to that of State Senate District 4 and State Senate District 4.
The state-senate districts whose fingerprint — 2000–2024 trajectory, demographics, ancestry, religion — sits closest to this one, and why.
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 →
Ohio 21st State Senate District. Akashic. https://akashic.app/sld-upper/39021/. Accessed May 20, 2026. License: CC BY 4.0.