LEWISTON, Maine - A two-day run, walk and bike fundraiser in Maine that was the brainchild of "Grey's Anatomy" star Patrick Dempsey has raised more than $1.1 million.

Proceeds from the "Dempsey Challenge" will benefit the Patrick Dempsey Center for Cancer Hope and Healing at Central Maine Medical Center in Lewiston.

On Sunday, Dempsey led a pack of riders through Lewiston. In all, more than 4,000 people registered for the bicycling, walking and running events held Saturday and Sunday.

Dempsey, who started the event last year, was spurred to action by his mother's experience battling cancer. He was born in Lewiston and grew up in nearby Turner and Buckfield.