100 Years of Chevy - Photo Gallery 10/44

FILE - In this March 19,2008 file photo, a Chevy Volt is on display during the Chevrolet news conference at the New York International Auto Show in New York. President Barack Obama's promise to put a million plug-in hybrid cars on the road by 2015 is fraught with problems, from engineering hurdles to the realities of the auto market and the economy. (AP Photo/Mary Altaffer, FILE)