General Motors sold 321 Chevrolet Volt cars, while, Nissan, its fiercest electric car competitor, has sold just 87 LEAF electric cars in the U.S. last month.
Production of both plug-ins are just getting off the ground, supplies are limited, and sales are still counted in the hundreds.
GM had originally planned to sell the Volt in only select areas of the country before 2012, but the automaker announced last week that it would expand sales of the Volt to all 50 states by the end of the year.
Nissan has said 20,000 people have put down $99 deposits to be put on a waiting list for the car.
The LEAF has a $32,780 base price while the Volt starts at $41,000. Both cars also are eligible for a federal tax credit that will cut their prices by $7,500.