As Stein notes, McCain voted against the 2005 energy bill. Obama supported it. I think it's worth reiterating that that bill was not well-received by environmentalists, and that it was also regarded as pork-laden. It also promoted a vast increase in the use of ethanol -- a product Obama has strongly supported -- in spite of its apparent negative environmental and third-world hunger-related effects.
It also wasn't popular in Oregon. The Oregonian had this to say about it: "Congress stages a depressing retreat, ditching the most meaningful conservation measures and embracing old-fashioned subsidies that fail to reverse U.S. dependence on foreign oil." (From a July 2005 editorial.)
Oregon voters should consider Obama's support of this bill -- which pleased neither conservatives nor environmental extremists -- when casting their votes.