2008Flipped from RepublicanFinal results
2008 election for U.S. Senate in Colorado
U.S. Senate · Colorado
Mark Udall (D) won with 52.8% of the vote, defeating Bob Schaffer (R) by 10.3 points, a seat Republicans won last time.
Mark UdallDemocrat · winner
52.8%1,230,994
Bob SchafferRepublican
42.5%990,755
Douglas "dayhorse" CampbellConstitution
2.6%59,733
Bob KinseyGreen
2.1%50,004
2,331,621 votes
Source: MIT Election Data and Science LabUpdated Sep 30, 2026, 7:25 AM ET
The seat over time
D − R margin in this seat's races around 2008
Races before and after
Source: MIT Election Data and Science LabUpdated Sep 30, 2026, 7:25 AM ET
Money in this race
Each line compares the two campaigns on one scale.
Mark UdallBob Schaffer
$11.8M
Raised by the campaign
$7.4M
$13M
Spent by the campaign
$7.2M
$61.9K
Cash on hand
$128.2K
Campaign money: FEC, through Dec 31, 2008.
Source: FEC campaign filingsUpdated Dec 31, 2008
The candidates
Mark Udall (D)Bob Schaffer (R)
Also on the ballot: Douglas "dayhorse" Campbell (Constitution), 2.6%; Bob Kinsey (Green), 2.1%