County record · fips 08059 · Colorado
JeffersonCO
Democratic ×5 since 2008reported 1880–2024 · 37 elections
The Long Record
37 elections against the Colorado and national vote
2024 result
D+20.0
won by Democrats
Record since first cycle
12–25
Dem–Rep two-party wins
Voted with the winner
24/37
65% of its elections
Closest election
1908
R+0.9
this countyColoradonational (official)dot colour = two-party winner · hollow = tie or unknown total · click a dot to open that election
The Biggest Swings
Cycle-over-cycle change in the two-party margin, in points
| Election | Swing | Toward |
|---|---|---|
| 1896 | +182.7 pts | Democrats |
| 1892 | -88.3 pts | Republicans |
| 1900 | -74.4 pts | Republicans |
| 1920 | -53.8 pts | Republicans |
| 1932 | +43.5 pts | Democrats |
Who Lives Here
Census & ACS county profile, 2024
Population
579,377
College (BA+)
52%
Median income
$110,656
2024 dollars
Non-white
25%
Rural
7%
Age 65+
18%
Interpolated between Census/ACS anchors; income CPI-deflated to 2024. Demographics begin in 2000 — earlier cycles have returns only.
Neighbouring counties
Adams, CO · Arapahoe, CO · Boulder, CO · Broomfield, CO · Clear Creek, CO · Denver, CO · Douglas, CO · Gilpin, CO · Park, CO