Hawaii 21st State Senate District, Hawaii: Democratic loyalist district. In 2024, voted D+22%. Democratic peak: D+57 in 1964.
Key facts
- 2024 presidential margin
- D+22MIT Election Lab
- Political archetype
- Democratic loyalistAkashic typology
- Population
- 38,5642024 5-year
- Median household income
- $106,1952024 5-year
- White (non-Hispanic)
- 18.4%2024 5-year
- Black
- 2.4%2024 5-year
- Hispanic / Latino
- 9.4%2024 5-year
- Peak Democratic margin
- D+57 in 1964MIT Election Lab
- Peak Republican margin
- R+27 in 1972MIT Election Lab
Constituent county margins for State Senate District 21, HIOne cell per constituent county, colored by 2024 presidential margin from deep red (Republican) through neutral to deep blue (Democratic), ordered bluest first.
R+60D+60
One cell per constituent county. Ordered by 2024 D-vs-R margin (bluest first). Hover for county-level numbers.
38 presidential elections
| Year | Won | Margin | Democratic | Republican | Total |
|---|---|---|---|---|---|
| D | 7,870 | 5,026 | 13,132 | ||
| D | 9,201 | 5,249 | 14,719 | ||
| D | 6,768 | 3,479 | 11,009 | ||
| D | 7,872 | 3,408 | 11,431 | ||
| D | 8,252 | 3,396 | 11,818 | ||
| D | 5,874 | 5,553 | 11,500 | ||
| D | 5,378 | 3,902 | 9,861 | ||
| D | 5,539 | 3,304 | 9,832 | ||
| D | 4,773 | 4,004 | 10,240 | ||
| D | 5,353 | 4,632 | 10,076 | ||
| R | 4,137 | 5,403 | 9,635 | ||
| R | 3,716 | 3,836 | 8,667 | ||
| D | 4,291 | 4,162 | 8,570 | ||
| R | 2,964 | 5,117 | 8,082 | ||
| D | 4,166 | 2,745 | 7,018 | ||
| D | 4,694 | 1,292 | 5,986 | ||
| D | 2,655 | 2,525 | 5,179 | ||
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Demographics
Race, ethnicity, and ancestry
Click any group to see the ancestries typically reported within it.
German
5.3%
English
4.3%
Irish
4.2%
Italian
1.8%
American
1.3%
French
1.0%
Polish
0.8%
Source · American Community Survey 5-year estimates, 2024 release. Hispanic/Latino is an ethnicity that overlaps the race categories, so these shares can total more than 100%. Ancestry is a self-reported, multiple-response item; ancestry percentages do not sum to the parent race percentage.
Age distribution by sex
Median age: 39.8 in this county, 39.1 nationally
Male
Age
Female
85+
75–84
65–74
55–64
45–54
35–44
25–34
18–24
5–17
<5
Source · American Community Survey 5-year estimates, 2024 release.
Median household income
2024 inflation-adjusted dollars
$106,195
State Senate District 21 ranks near the middle of US counties.
State Senate District 21$106,195
Hawaii$100,389
United States$80,734
Source · American Community Survey 5-year estimates, 2024 release.
Poverty rate
All persons below federal poverty line
9.2%
Child poverty is below the national average.
Children under 1811.3%
Working age (18–64)8.6%
Seniors (65+)9.5%
Source · American Community Survey 5-year estimates, 2024 release.
Language at home
Population aged 5 and older
74.0%
speak English only
Asian & Pacific Islander22.2%
Spanish2.0%
Other Indo-European1.2%
Other languages0.7%
Source · ACS 5-year estimates, 2024.
Religious adherents
Adherents per capita by tradition
Source · 2020 US Religion Census. Remaining 61.6% of residents not counted as adherents by any reporting body.
Anchored in urban Honolulu, this district delivers presidential margins exceeding 40 points, reflecting a dense, heavily Democratic electorate that has shown little competitive variation in recent cycles.
The Democratic margin in Hawaii 21st State Senate District reached its widest at fifty-seven points in 1964. The margin in 2024 was twenty-two points — still decisive.
Its loyalty is rooted in its place. Median household income of $106,195, a 18% non-Hispanic-white share, and a population of 38,564 together describe a district whose political habits are deeply settled.
Compare two places, side by side
Twelve curated comparisons line up election history, demographics, and the divergence story for two places at a glance. Browse all comparisons →
Cite this page
All citations released under CC BY 4.0. Attribution: Akashic Intelligence.
State Senate District 21, Hawaii. Akashic. https://akashic.app/sld-upper/15021/. Accessed May 20, 2026. License: CC BY 4.0.
License: CC BY 4.0
Frequently asked questions
How did State Senate District 21, Hawaii vote in 2024?
In 2024, State Senate District 21, Hawaii voted Democratic by 21.7 points (D+22), carried by the Democratic candidate. Out of 13,132 votes cast, 7,870 went Democratic and 5,026 went Republican.
What is State Senate District 21, Hawaii's political archetype?
Akashic classifies State Senate District 21, Hawaii as a "Democratic loyalist" district based on its long-arc presidential voting pattern. Across 38 elections in the dataset, the district has voted Democratic 14 times, Republican 3 times, and other 0 times.
When did State Senate District 21, Hawaii last vote Republican?
The most recent presidential election in which State Senate District 21, Hawaii voted Republican was 1984.
How many people live in State Senate District 21, Hawaii?
State Senate District 21, Hawaii has a population of 38,564 according to the 2024 American Community Survey 5-year estimates from the US Census Bureau.
What is the median household income in State Senate District 21, Hawaii?
Median household income in State Senate District 21, Hawaii is $106,195 — above the national median of $80,734. The Hawaii state median is $100,389.
What is the political history of State Senate District 21, Hawaii?
Akashic tracks 38 presidential elections in State Senate District 21, Hawaii from 1876 to 2024. Of those, 14 went Democratic and 3 went Republican. The district's archetype — "Democratic loyalist" — captures the overall trajectory of that voting record.