Colorado State Senate seat · lines in effect since 2022
Colorado Senate District 18
A district of about 143,000 people, 75% of adults with a bachelor's degree. It votes D+70.3 relative to the nation for president.
2024 election
Nov 5, 2024- Judy Amabile (D) · won90.5%
- Gary Swing (OTH)9.5%
Source: MIT Election Data and Science LabUpdated Sep 30, 2026, 12:13 PM ET
Where it sits among all 35 seats
Every Colorado State Senate seat by partisan lean, from most Democratic to most Republican. Lean is the seat's presidential vote on current lines, relative to the nation.
Democratic
Source: 99chambers: 2024 and 2020 presidential results on current lines, relative to the nation (2024 weighted 3:1)Updated Oct 16, 2026, 5:19 AM ET
Every election for this seat
14 races since 1968. District numbers are redrawn after each census: each group is one set of lines.
| Year | Winner | Runner-up | Won by |
|---|---|---|---|
| Lines first used in 2022 | |||
| 2024 | Judy Amabile (D) | Gary Swing (I) | 80.9 |
| Lines first used in 2012 | |||
| 2020 | Steve Fenberg (D) | Peg Cage (R) | 65.8 |
| 2016 | Steve Fenberg (D) | M. Peter Spraitz (R) | 59.2 |
| 2012 | Rollie Heath (D) | Barry P. Thoma (R) | 56.7 |
| Lines first used in 2002 | |||
| 2008 | Rollie Heath (D) | — | Unopposed |
| 2004 | Ron Tupa (D) | Krista Poch (R) | 56.7 |
| Lines first used in 1992 | |||
| 2000 | Ron Tupa (D) | Steven M. Hatfield (R) | 50.3 |
| 1996 | Dorothy Rupert (D) | Susan Kolwicz (R) | 44.1 |
| 1992 | Jana Mendez (D) | — | Unopposed |
| Lines first used in 1982 | |||
| 1988 | Jana Mendez (D) | Robert M. Wells (R) | 23.1 |
| 1984 | Jana Mendez (D) | Bob Shonkwiler (R) | 4.5 |
| Lines first used in 1972 | |||
| 1978 | Polly Bacabarragan (D) | — | Unopposed |
| 1974 | Eldon W. Cooper (D) | D. F. Renshaw Sr. (R) | 47.1 |
| Lines first used in 1962 | |||
| 1968 | Don Macmanus (D) | Moses Cisneros (R) | 34.4 |
Won by: the winner's lead over the runner-up, in points of the vote. Source: 99chambers results archive (MEDSL, Klarner, state election offices)
Districts that overlap District 18
The state's districts in other chambers that share residents with this one, and the share of District 18's area in each.
- U.S. House
- CO-2 100%
Every race on these lines
Results recomputed from precinct returns as if today's boundaries had always existed, so years compare like for like.
| 2016 | 2018 | 2020 | 2024 | |
|---|---|---|---|---|
| President | D+63.6 | No race | No race | D+68.0 |
| U.S. Senate | D+57.5 | No race | D+65.9 | No race |
| Governor | No race | D+67.9 | No race | No race |
Outlined: the race for this seat itselfBlank: no race that year
Source: 99chambers results archive: precinct results allocated to current lines; 2026: civicAPIUpdated Nov 8, 2026, 7:01 PM ET
Who lives here, compared
Grey bars show the spread of all 35 seats. Small marks are other seats in Colorado. The black marker is District 18.
Highest of 35 seats.
Lower than 91% of seats.
Lower than 94% of seats.
Lower than 76% of seats.
Higher than 94% of seats.
Denser than 59% of seats.
Source: Census Bureau, American Community Survey 2020–2024 5-year estimates, allocated to current linesUpdated Oct 13, 2026, 5:06 AM ET
Seats most like this one
Nearest seats on demographics, density and lean.
District 3172% college gradsD+66.7Not up in 2026District 14
60% college gradsD+43.5Not up in 2026District 17
21% Hispanic · 55% college gradsD+40.3Not up in 2026District 32
30% Hispanic · 50% college gradsD+50.1Held D
Source: Census Bureau, American Community Survey 2020–2024 5-year estimates, allocated to current lines; 99chambers: 2024 and 2020 presidential results on current lines, relative to the nation (2024 weighted 3:1)Updated Oct 16, 2026, 5:19 AM ET