Patrick Dempsey has signed up a trio of cycling superstars for his second annual fundraising race in his native Maine.
 
Olympians and Tour de France veterans Levi Leipheimer and George Hincapie and this year's top U.S. Tour de France finisher, Chris Horner, will join the star for his 100-mile Dempsey Challenge on October 3.
 
Dempsey launched the Challenge last year to raise money for the Patrick Dempsey Center for Cancer Hope & Healing at Central Maine Medical Center in Lewiston.

See more photos of Patrick here!