Mark Ruffalo had a big smile on his face as he signed ticket stubs and posed for pictures at Chicagoland Speedway. Ruffalo felt right at home at his second NASCAR race. This is what my people are like.'' Ruffalo, 46, served as the grand marshal for Saturday night's Nationwide Series stop, but he also came out to support Leilani Munter in the ARCA race. Ruffalo and Stanford professor Mark Jacobson helped create the organization in 2011 to advocate for the transition to 100 percent clean, renewable energy. More...