"It's going to take an ‘energy president' to lead this country, and I'm the man for the job," says New Mexico governor Richardson. Indeed, the man who served as President Clinton's secretary of energy has been serving up some of the most creative green ideas yet.

Battle Cry: "I believe very strongly in what John F. Kennedy asked all Americans to do—sacrifice a little bit for the collective good. It's in our national interest to reduce our consumption of fossil fuels."

Green Chops: In 2004, Richardson and California's Schwarzenegger laid the groundwork for the Clean and Diversified Energy Initiative, which promotes clean energy in 19 western states. If elected, Richardson would pursue national light-rail and bullet-train systems and create a new cabinet position, secretary of water, to oversee drought and water-supply challenges.

Power Points: Calls for fuel-economy standards of 50 mpg by 2020 and a 90 percent reduction in national greenhouse-gas emissions by 2050; wants the country to generate half of its electricity from renewable sources by 2040.

Outside Moment: "Kicking around the mountains of northern New Mexico with my horse, Sundance, is my main recreational activity," says Richardson.

Eco-Hero: Congressman Morris Udall, who represented Arizona from 1961 to 1991. "He was a western environmentalist," says Richardson. "I patterned myself after him."

Hmmm: Between 2001 and 2002, Richardson served on the boards of three North American oil companies: Diamond Offshore Drilling, Venoco Inc., and Valero Energy Corporation. He sold more than $100,000 in Valero stock in May 2007.