Colorado's 18th Senate district

Colorado's 18th Senate district is one of 35 districts in the Colorado Senate. As of January 8, 2025 it is represented by Judy Amabile.^[3] It was previously represented by Democrat Steve Fenberg, the former Senate President, since 2017.^[4]

Colorado's 18th State Senate district
From 2022 onward From 2012 to 2022
Senator	Judy Amabile D–Boulder
Registration	44.4% Democratic 7.2% Republican 46.7% No party preference
Demographics	83% White 1% Black 9% Hispanic 4% Asian 3% Other
Population (2018)	151,796[1]
Registered voters	119,505[2]

Geography

District 18 is based in the city of Boulder, also covering the outlying Boulder County communities of Lyons, Nederland, Gunbarrel, and Niwot.^[5][6]

The district is located almost entirely within Colorado's 2nd congressional district, with a small section extending into the 4th district. It overlaps with the 10th, 11th, 12th, and 13th districts of the Colorado House of Representatives.^[7]

Recent election results

Colorado state senators are elected to staggered four-year terms; under normal circumstances, the 18th district holds elections in presidential years.

2020

2020 Colorado State Senate election, District 18^[8]

Party		Candidate	Votes	%
	Democratic	Steve Fenberg (incumbent)	75,261	82.9
	Republican	Peg Cage	15,524	17.1
Total votes			90,785	100
	Democratic hold

2016

2016 Colorado State Senate election, District 18^[9]

Party		Candidate	Votes	%
	Democratic	Steve Fenberg	67,799	79.6
	Republican	M. Peter Spraitz	17,370	20.4
Total votes			85,169	100
	Democratic hold

2012

2012 Colorado State Senate election, District 18^[10]

Party		Candidate	Votes	%
	Democratic	Rollie Heath (incumbent)	66,619	78.3
	Republican	Barry Thoma	18,427	21.7
Total votes			85,046	100
	Democratic hold

Federal and statewide results

Year	Office	Results[11]
2020	President	Biden 83.6 – 14.4%
2018	Governor	Polis 82.7 – 15.2%
2016	President	Clinton 78.1 – 15.2%
2014	Senate	Udall 77.5 – 19.4%
	Governor	Hickenlooper 75.6 – 18.1%
2012	President	Obama 76.5 – 21.0%