Idaho 18th State Senate District · the strongest Democratic and Republican presidential performances recorded here, measured three ways.
1892–2024 · 34 presidential cycles
Highest vote share
Largest share of the presidential candidate vote cast here.
Democratic
William J. Bryan1896
76.9%
247 votes · D+53.9 · modeled estimate
Runner-up · Franklin D. Roosevelt, 1936 · 71.7%
Republican
Ronald Reagan1984
59.5%
4,793 votes · R+20.6 · modeled estimate
Runner-up · Dwight D. Eisenhower, 1952 · 59.4%
Most votes
Largest number of votes cast for the party’s presidential nominee here.
Democratic
Joe Biden2020
16,190votes
61.1% of the vote · D+25.5 · modeled estimate
Runner-up · Kamala Harris, 2024 · 14,986 votes
Republican
Donald Trump2020
9,435votes
35.6% of the vote · D+25.5 · modeled estimate
Runner-up · Donald Trump, 2024 · 9,280 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
William J. Bryan1896
+60.0pts D vs U.S.
Place D+53.9 · U.S. R+6.1 · modeled estimate
Runner-up · William J. Bryan, 1908 · +30.6 pts
Republican
Benjamin Harrison1892
+37.5pts R vs U.S.
Place R+35.8 · U.S. D+1.7 · a third-party candidate carried the Place · modeled estimate
Runner-up · Richard Nixon, 1968 · +15.1 pts
current representation
Current officeholders
DJanie Ward-EngelkingState Senate · 18
State legislative officeholder from OpenStates nightly current-legislator data.
U.S. House elections · 3 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
R
41.1%11,276
58.9%16,163
27,439
2020
R
43.7%10,743
56.3%13,863
24,606
2018
R
47.6%8,628
52.4%9,517
18,145
Idaho Senate District 18 covers a dense slice of Ada County where the 2024 presidential margin reached D+22.8 — an outlier in a state that leans heavily Republican statewide, reflecting the district's younger, college-educated urban electorate.
Across the recorded series it reached a Democratic high of 53.9 points in 1896 and a Republican high of 35.8 points in 1892. Between 2020 and 2024 the district moved 2.8 points toward the Republican candidate; the 2024 margin was 22.7 points.
A population of 51,948, a 79% non-Hispanic-white share, and a median household income of $100,140 describe the district. The district's voting pattern over the last decade is most similar to that of State Senate District 16 and State Senate District 17.
Akashic
Political twins — state-senate districts
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.
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.
Idaho 18th State Senate District. Akashic. https://akashic.app/sld-upper/16018/. Accessed May 20, 2026. License: CC BY 4.0.
How did Idaho 18th State Senate District vote in 2024?
In 2024, Idaho 18th State Senate District voted Democratic by 22.7 points (D+22.7), carried by the Democratic candidate. Out of 25,097 votes cast, 14,986 went Democratic and 9,280 went Republican.
When did Idaho 18th State Senate District last vote Republican?
The most recent presidential election in which Idaho 18th State Senate District voted Republican was 2000.
How many people live in Idaho 18th State Senate District?
Idaho 18th State Senate District has a population of 51,948 according to the 2024 American Community Survey 5-year estimates from the US Census Bureau.
What is the median household income in Idaho 18th State Senate District?
Median household income in Idaho 18th State Senate District is $100,140 — above the national median of $80,734. The Idaho state median is $77,800.
What is the political history of Idaho 18th State Senate District?
Akashic tracks 38 presidential elections in Idaho 18th State Senate District from 1876 to 2024. Of those, 20 went Democratic and 13 went Republican.