Pennsylvania 166th State House 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
Joe Biden2020
63.0%
26,432 votes · D+27.0 · modeled estimate
Runner-up · Kamala Harris, 2024 · 61.5%
Republican
Calvin Coolidge1924
81.7%
5,303 votes · R+69.2 · modeled estimate
Runner-up · Theodore Roosevelt, 1904 · 77.4%
Most votes
Largest number of votes cast for the party’s presidential nominee here.
Democratic
Joe Biden2020
26,432votes
63.0% of the vote · D+27.0 · modeled estimate
Runner-up · Kamala Harris, 2024 · 26,092 votes
Republican
Richard Nixon1972
22,108votes
64.3% of the vote · R+30.2 · modeled estimate
Runner-up · Ronald Reagan, 1984 · 20,448 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
Kamala Harris2024
+25.4pts D vs U.S.
Place D+23.9 · U.S. R+1.5 · modeled estimate
Runner-up · Joe Biden, 2020 · +22.6 pts
Republican
Herbert Hoover1932
+56.9pts R vs U.S.
Place R+39.1 · U.S. D+17.8 · modeled estimate
Runner-up · William McKinley, 1896 · +45.4 pts
current representation
Current officeholders
DGreg VitaliState House · 166
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.
Source · Akashic county-allocated estimate from certified county returns, House; not precinct-counted.
Year
Vote lead
Democratic
Republican
Total
2024
D
62.9%22,183
37.1%13,067
35,250
2018
D
62.0%16,808
38.0%10,317
27,125
With a 2024 presidential margin of D+23.9, District 166 ranks among Pennsylvania's more reliably one-sided legislative seats, reflecting the dense urban or inner-suburban demographics typical of the Philadelphia region.
Across the recorded series it reached a Democratic high of 27.0 points in 2020 and a Republican high of 69.2 points in 1924. Between 2020 and 2024 the district moved 3.1 points toward the Republican candidate; the 2024 margin was 23.9 points.
A population of 63,022, a 84% non-Hispanic-white share, and a median household income of $129,586 describe the district. The district's voting pattern over the last decade is most similar to that of State House District 165 and State House District 168.
Akashic
Political twins — state-house districts
The state-house 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.
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 → · Or open the source-auditable district brief for electoral baseline, electorate, current-cycle coverage, geography, official dates, and methodology. Open campaign intelligence report →
Cite this page
All citations released under CC BY 4.0. Attribution: Akashic Intelligence.
Pennsylvania 166th State House District. Akashic. https://akashic.app/sld-lower/42166/. Accessed May 20, 2026. License: CC BY 4.0.
How did Pennsylvania 166th State House District vote in 2024?
In 2024, Pennsylvania 166th State House District voted Democratic by 23.9 points (D+23.9), carried by the Democratic candidate. Out of 42,430 votes cast, 26,092 went Democratic and 15,934 went Republican.
When did Pennsylvania 166th State House District last vote Republican?
The most recent presidential election in which Pennsylvania 166th State House District voted Republican was 1988.
How many people live in Pennsylvania 166th State House District?
Pennsylvania 166th State House District has a population of 63,022 according to the 2024 American Community Survey 5-year estimates from the US Census Bureau.
What is the median household income in Pennsylvania 166th State House District?
Median household income in Pennsylvania 166th State House District is $129,586 — above the national median of $80,734. The Pennsylvania state median is $77,971.
What is the political history of Pennsylvania 166th State House District?
Akashic tracks 38 presidential elections in Pennsylvania 166th State House District from 1876 to 2024. Of those, 10 went Democratic and 27 went Republican.