General election
- Mark Baisley Republican
state senator from the 4th district (2023–present) (previously ran for governor)
- Clinton Roosevelt Dale Independent
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- Joshua William Kuebler Independent
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- Democrat Nominee TBD
Democratic primary
- John Hickenlooper Incumbent
incumbent U.S. senator
state senator from the 34th district (2019–present)
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college professor, candidate for U.S. Senate in 2022, and candidate for in 2024
Republican primary
state senator from the 4th district (2023–present) (previously ran for governor)
business owner
AI strategic advisor
former state representative from the 16th district (2011–2017) and candidate for Colorado's 8th congressional district in 2024
Montrose County commissioner