Staggered Senate
Senators serve four-year terms; about half the seats are on the ballot each election.
Colorado › Colorado State Senate · November 3, 2026 · Updated Oct 16, 2026
Colorado State Senate District 20
Lieder is very likely to win: Lieder wins in more than 99 of every 100 simulations.
Lieder (D)
>99%
chance of winning
Mancuso (R)
<1%
- Average margin
- D+24.4
- 80% of outcomes
- D+15 to D+34
- Partisan lean
- D+17
- Polls
- No pollsmodel only
Lieder is very likely to win: Lieder wins in 49 of every 50 simulations.
Lieder (D)
98%
chance of winning
Mancuso (R)
2%
- Average margin
- D+21.5
- 80% of outcomes
- D+9 to D+34
- Partisan lean
- D+17
- Polls
- No pollsmodel only
How this race is decided
Range of outcomes
Final margin across our simulations; the white dashes mark the middle 80%.
The candidates
Democratic
Sheila Lieder
Republican
Richard Mancuso
What goes into the forecast
Every ingredient's estimate of the final margin.
- National environment
- D+9.5Election Day forecast
- Colorado state offices
- +0.0Polls for governor, statewide and legislative races · details
- Environment here
- D+9.5Used by the fundamentals
- Swing reaching this office
- 58%Of a shift in the environment, from past legislative races since 2016
- Mountain West adjustment
- +1.2How legislative races in the region have run against lean and environment lately
Each estimate is a margin before national and statewide uncertainty is simulated. Horizon blends polls, fundamentals and a little of the similar-places estimate, weighting each by how precise it is; Pulse uses polls and similar places only.
Fundamentals inputs
| Incumbency (+1 D, −1 R) | 0 |
| Fundraising edge (log ratio of individual money) | 1.03 |
| Elected-experience edge | 0.67 |
| First-term incumbent | 0 |
| Seat's last result vs. expectation | -3.73 |
| Incumbent's last result vs. expectation | 0 |
Polls
No public polls of this race. The forecast relies on fundamentals and on polling of similar places in the state.
The district
Lean D+17: how much more Democratic or Republican than the nation it votes for president.
Presidential vote
Precinct results re-aggregated to the current district lines.
Who lives here
- Population
- 171,737
- People per km²
- 241
- Adults with a B.A.+
- 57%
- White, no degree
- 32%of adults
- White 79%
- Hispanic 13%
- Black 1%
- Asian 3%
- Other / multiracial 5%
American Community Survey 2020–2024, aggregated from census tracts.
Past results
Results in the same-numbered district; earlier elections may have used different lines.
2024 President Vote in this district
106,361 two-party votes · D+17.8 · D+19.3 vs. the nation✓ Kamala Harris (D)58.9%
Donald Trump (R)41.1%
2022
91,069 votes · D+10.9✓ Lisa A Cutter (D)54.2%
Tim Walsh (R)43.5%
Betterose Ryan (L)2.2%
2020 President Vote in this district
111,029 two-party votes · D+16.3 · D+11.7 vs. the nation✓ Joe Biden (D)58.1%
Donald Trump (R)41.9%
2018 Earlier district lines
92,315 votes · D+12.2✓ Jessie Danielson (D)54.1%
Christine Jensen (R)42.4%
Charles Messick (L)3.5%
2016 President Vote in this district
89,524 two-party votes · D+5.7 · D+3.5 vs. the nation✓ Hillary Clinton (D)52.9%
Donald Trump (R)47.1%
2014 Earlier district lines
71,665 votes · D+0.7✓ Cheri Jahn (D)46.8%
Larry Queen (R)46.2%
Chris Heismann (L)7.0%