U.S. Senate · All Colorado races

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John Hickenlooper

Democratic · incumbent

99 in 100

chance of winning, out of 100

Mark Baisley

Republican

1 in 100

John Hickenlooper wins in 99 of 100 simulations.

There are no qualifying public polls yet, so the forecast leans on fundamentals; partisan lean, the national environment and incumbency point to John Hickenlooper +25.0.

Where the result could land

Every simulated outcome, grouped in 2-point steps. Projected margin Hickenlooper +25.1; 80 in 100 fall between Hickenlooper +10.7 and Hickenlooper +39.3.

The candidates

Mark Baisley

Republican · American politician (born 1955)

Mark Baisley is an American politician who is a state senator from Roxborough Park, Colorado. A Republican, Baisley represents Colorado's 4th Senate district. Previously, he represented Colorado House of Representatives District 39, which encompassed parts of Douglas County and all of Teller County. Wikipedia

Raised

$138K

Cash on hand

$28K

Through 2026-09-30

John HickenlooperIncumbent

Democratic · American politician (born 1952)

John Wright Hickenlooper Jr. is an American politician, geologist, and businessman serving as the junior United States senator from Colorado since 2021. A member of the Democratic Party, he served as the 42nd governor of Colorado from 2011 to 2019 and as the 43rd mayor of Denver from 2003 to 2011. Wikipedia

Raised

$11.5M

Cash on hand

$2.3M

Through 2026-09-30

Official website ↗

Christopher Baum

Approval Voting

Bob Chew

Forward

Blake Huber

Libertarian

Adam Withrow

Unity

Ballot list and short bios from Wikipedia (CC BY-SA); websites from Wikidata; fundraising from the FEC (cycle-to-date, latest report).

What if this race flips? Try it in the map builder →

Polls

No public polls have tested John Hickenlooper against Mark Baisley yet.

No polls of this matchup yet, so there is no polling average. The forecast relies on fundamentals.

Chance of winning over time

How this race’s odds have moved as polls and the national environment changed.

Hickenlooper +1 over the past 3 months

Out of 100. Today: Hickenlooper 99, Baisley 1.

What’s driving the forecast

The model blends each estimate by how much to trust it right now. Polls get 0% of the weight, 15 days out.

Polling average (after adjustments)	—	no polls
Partisan lean (Cook PVI, 2026 lines)	D+6.0	roughly 12 points of margin vs. the nation
National environment	D+9.6	generic ballot + presidential approval
Incumbent’s track record	Baisley +2.1	In 2020 they ran 4.2 pts more Republican than the state’s lean predicted; half carries over (max 10)
Incumbency	Hickenlooper +3.0	incumbent’s side
Fundamentals estimate	Hickenlooper +25.0	±11 typical error
Expert ratings (average)	Hickenlooper +22.0	used only in the “+ Expert ratings” version
Forecast	Hickenlooper +25.0	±11.2 standard deviation, including 2.3 for movement before Election Day

All three versions

Polls only: John Hickenlooper 99 in 100 (Solid D)
Polls + fundamentals: John Hickenlooper 99 in 100 (Solid D)
Polls + fundamentals + experts: John Hickenlooper >99 in 100 (Solid D)

Published ratings

Other forecasters’ ratings, as listed on Wikipedia. Shown for comparison; they feed only the “+ Expert ratings” version.

Cook: Solid DDDHQ: Safe DThe Economist: Safe DSplit Ticket/FPO: Safe DFox News: Solid DInside Elections: Solid DRCP: Solid DSabato: Safe DSilver Bulletin: Solid DSplit Ticket: Safe D

County map

Counties colored by the 2024 presidential vote; on election night this switches to the live count in this race.

Color shows the 2024 presidential margin in each county. Hover or tap a county for its numbers.

2024 results: Fox News 2024 county results, compiled by Tony McGovern (github.com/tonmcg/US_County_Level_Election_Results_08-24). Not authoritative.

Rules and notes

Last polls close at 9 pm Eastern.
Last election: 53.50% D
Incumbent renominated

Senate races, closest first · this is #19 of 35