Van Garderen, the 25-year-old BMC rider from Bozeman, Montana, led the race for the final four days, finishing 1 minute, 30 seconds ahead of Swiss Mathias Frank. The Tour of California winner in May, van Garderen was fifth last year in the Tour de France, then slipped to 45th this year.

American Tom Danielson of Team Garmin-Sharp was third overall, 1:42 behind van Garderen.

Slovakia's Peter Sagan won the final leg for his fourth stage victory of the week, completing the eight-lap, 72.4-mile circuit race in 2:27:15. Canada's Ryan Anderson of Optum-Kelly Benefit was second, a bike-length behind. Alessandro Bazzana of UnitedHealthcare was third.

Van Garderen, who finished third in USA Pro Challenge in 2011 and second last year, when to the front of the field briefly in the final half-mile to avoid potential crashes. Sagan want to the front in the final 200 yards and eased at the line with his 19th win of the season.

"July is definitely the most important month in bike racing," said van Garderen, who went to the high school in Colorado and developed his early career while riding throughout the Rocky Mountains. "I had an incredible time here in Colorado. Being able to race on the roads I used to train on in high school, that was a dream. I was hearing my name called out so many times, it was unbelievable. So this is a special race for me." Despite his two titles this year, van Garderen stressed his desire fare well in the Tour de France.

"This doesn't make up for a poor July," said van Garderen, who the past two years rode in the Tour de France in support of teammate Cadel Evans of Australia, the 2011 race winner. "I'm still hungry for the Tour. I still see myself as a Grand Tour rider and I want to come back to the Tour in the future and fight for a high GC (leader's finish) and hopefully a couple of years down the line even wear the yellow jersey there."

Christopher Juul Jensen (Saxo-Tinkoff) of Denmark and Joshua Edmondson (Sky) of Great Britain crashed approaching the final lap toward the back of the field. Jensen finished the race, but Edmondwson withdrew.

Van Garderen became the race's third leader with a runner-up mountaintop finish in the fourth stage, the most difficult of the race. He won the time trial fifth stage by 4 seconds to extend his lead, then maintained it for the final two days.

Reigning Tour de France champion Chris Froome of Great Britain, who suffered in the altitude since the opening stage, withdrew early in the final stage.

Defending race champion Christian Vande Velde (Garmin-Sharp) finished 21st overall after a main pack finish.

The race's third edition began August 19 in Aspen with 16 teams and 128 riders. The 593-mile event ended with 108 riders after 20 cyclists withdrew following injuries or illness.

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