Elia Viviani of Cannondale has won the fourth stage of the US Pro Tour Challenge.
The fourth stage was a 113km stage or four laps of a circuit, in Colorado Springs.
Twelve riders in Jens Voigt (Trek Factory Racing), Laurent Didier (Trek Factory), Gregor Muhlberger (NetApp-Endura), Ruben Zepuntke (Bissell Development), Rob Britton (SmartStop), Oscar Clark (Hincapie Sportswear Development), Toms Skujins (Hincapie Sportswear Development), Steve Fisher (Jelly Belly), Ben Jacques-Maynes (Jamis), Adam Phelan (Drapac), Danny Summerhill (UnitedHealthcare) and Martijn Verschoor (Novo Nordisk) broke away and took a lead of 3.40.
Ben Jacques-Maynes took the three two climbs but just after the third climb in which Jens Voigt had been second, the Trek Factory rider stormed away to huge cheers from the crowds.
With twenty kilometres left, Voigt was 2.05 ahead of the chasers and 2.10 ahead of the peloton who were just starting on the fourth climb - the Garden Of The Gods.
Voigt flew over the summit and started on the descent with seventeen kilometres to go and a minute knocked off his lead.
Trek started to put riders on the front of the peloton to slow things down and allow Voigt who is retiring on Sunday a bit of time.
BMC put race leader Tejay van Garderen on the front to stay out of trouble as the gap to Voigt dropped to 35 seconds with 4.5kms left.
The fledgling American teams like Hincapie, and United HealthCare were hunting down Voigt, against orders which had come from the World Tour teams .
Taking the final bend, the peloton had Voigt in sight and with seven hundred metres to go, Voigt was passed.
Elia Viviani of Cannondale put in a superb push and took the victory in 2.28.52 ahead of Martin Kohler of IAM Cycling and Sergei Tvetcov, followed by Magner, Reijnen, Kocjan, Howes, Cantwell, Bookwalter and Anderson.
Speaking to his team, Jens Voigt said: "I don't think I could have done it any differently. It's how I race."
Tejay van Garderen of BMC continues to lead the race.