The Nissan Leaf has turned heads as the country's first mass-produced fully-electric vehicle, but it appears the model may fall short of the sales expectations originally set by Nissan.

The Japanese automaker estimated that it would sell at least 20,000 of the model by the end of the year, but revised projections are finding that the final total will likely be closer to half of that, with Automotive News reporting that Nissan now expects 10,000 to 12,000 Leafs sold.

"It's different than anything we've ever done, launching the car in three global markets at the same time," said Al Castignetti, Nissan VP of sales. "We knew it wasn't going to be easy."

In order to even purchase a Leaf, drivers must submit a request through a reservation system, which requires a $99 deposit. The system filled up with 20,000 requests back in September 2010, but Nissan has since found that many are not ultimately pulling the trigger on the purchase – only 46 percent are taking delivery.

The good news for Nissan is that the car is not yet available in all markets – so some of these reservations are in cities that don't have the Leaf yet. The company has also opened up the system again to accept more orders for the vehicle.