Gas prices flying past $4 a gallon have played a big part in a surge in sales of hybrid and electric cars, including the Chevrolet Volt. In March, General Motors Co. set a monthly sales record of 2,289 for the Volt, an electric car with a small backup gas engine. It sold just 7,671 Volts last year. (Associated Press)

Gas prices flying past $4 a gallon have played a big part in a surge in sales of hybrid and electric cars, including the Chevrolet Volt. In March, General Motors Co. set a monthly sales record of 2,289 for the Volt, an electric car with a small backup gas engine. It sold just 7,671 Volts last year. (Associated Press)