A 9.0-magnitude earthquake that rocked Japan in March could delay the start of U.S. production of the Nissan Leaf electric vehicle until late 2012, according to Automotive News.

The costs of getting production back up and running in Japan after the massive earthquake and tsunami forced Nissan to take its Japanese production plant offline. The company was slated to build a production plant for the Nissan Leaf in Smyrna, Tenn., that will produce up to 150,000 Leaf vehicles every year. Those plans have been pushed back until December next year, according to Automotive News.

Production of the Leaf has been stalled several times in the past six months, due to a glitch in the air conditioning system and the earthquake among other issues. The ambitious electric vehicle has a relatively low price tag (by EV standards) — still a hefty $33,000 — and is designed to attract a wider swath of drivers to the electric car market. It’s labeled by Kelly Blue Book as the first electric car for the masses.

Nissan’s Leaf sales were more than double that of the Volt in May, with the company selling 1,142 cars in the month. General Motors sold 481 Volts, which is about the same as the 493 Volts it shipped in April. But sales likely didn’t grow as quickly as the Leaf because General Motors said it was pulling back on its Volt supply to issue more demonstration cars to dealerships. The 2011 Nissan Leaf sells for $32,780, while the 2011 Chevy Volt cost around $41,000 prior to the price cut. Electric car buyers can apply for a federal tax credit that can bring the price down by $7,500.

The higher sales are an accomplishment for Nissan, which regularly faces hurdles in bringing the Leaf to the United States. The company said it is on track to deliver 20,000 Nissan Leaf cars to people who have reserved them by September. General Motors has shipped around 1,700 Volts since the vehicle went on sale last year, while Nissan has shipped around 1,000 Leafs.

Nissan recently went on the offensive by taking a shot at the Volt in a television advertisement. Sales of both electric cars have also been neck-and-neck for the past five months and only differ by around 17 cars shipped. As of the end of May, Nissan had sold 2,184 Leafs while General Motors had sold 2,167 Volts. The Leaf is cheaper than the Volt, but it also can’t travel anywhere near as far as the Volt and takes a while to recharge.

The U.S. government has set ambitious targets for both the Volt and Leaf, based on its goal of having more than 1 million electric cars on the road by 2015. The U.S. government expects GM to sell around 500,000 Volts by 2015 and Nissan to sell 300,000 Leafs by 2015.