Car sales overall continued their upward trend last month, but sales of plug-in cars soared in March to more than 3,800 units.

The bulk of those sales came from a resurging Chevy Volt, which logged its highest-ever single-month sales figure, along with the debut of the Toyota Prius Plug-In Hybrid.

More plug-ins in total were sold last month than in any month since December 2010, when the Nissan Leaf and the Chevy Volt--the first two mass produced electric cars of the modern era--went on sale.

Sales of the Chevrolet Volt spiked from the February total of 1,023 to 2,289, for a total of 3,915 sold so far this year. The comparable figure for January through March 2011 was just 1,210.

Volt sales were likely helped by the arrival of 2012 Volt models that qualify for solo travel in California's High Occupancy Vehicle (HOV) lanes, which went on sale in the state last month.

Nissan Leaf sales too climbed, from February's 478 to 579 last month, for a three-month total so far this year of 1,733. In 2011, that figure was only 452.

Remarkably, Toyota sold 891 Prius Plug-In Hybrids in that car's first full month on the market--or about 3 percent of the 28,711 Priuses sold in March.

The plug in Prius is the third and newest high-volume plug-in car to go sale; 7 of them also found buyers in the very last days of February.

2012 Toyota Prius Plug-In Hybrid, production version road test, San Diego, CA, Jan 2012

2012 Toyota Prius Plug-In Hybrid, production version road test, San Diego, CA, Jan 2012

Other plug-ins sold during the month include the Mitsubishi 'i', which logged 56 sales for a three-month total of 136.

For the second month in a row, Ford sold no 2012 Focus Electric hatchbacks. It logged 2 sales in January, and 10 delivered last December.

We also presume there were deliveries of the Coda Sedan--since the company publicized its first sales last month.

As usual Fisker Automotive declined to provide sales of its Karma range-extended electric car.

Tesla Motors reports global sales every quarter, and we'll learn later in the month how many of their dwindling supply of Roadsters the company sold from January through March.

As we noted last week, electric car sales will rise--but it will be slow. Still, the stellar March results following a new February high give some hope that far more electrics will be sold during 2012 than in 2011.


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