Sales of plug-in electric cars in April continued at roughly the same pace as in March, with sales likely totaling about 7,500 cars.

Last year's first- and third-place plug-ins, the Chevy Volt and Nissan Leaf, are now pacing each other in sales. Their year-to-date totals are separated by less than 100 units.

Meanwhile, we simply don't know whether the Tesla Model S continued to be the best-selling electric car in the U.S.

Leaf and Volt neck-and-neck

The Chevrolet Volt sold 1,306 units in April, bringing its total to 5,550 for the first four months of the year.

Chevy's range-extended electric vehicle was by far the best-selling plug-in car last year, with more than 23,000 sold.

But the Nissan Leaf is now in full production in Tennessee, and 1,937 Leafs were delivered to buyers last month.

That brings Nissan's total to 5,476 for the year to date, virtually neck-and-neck with the Volt for the first time since 2011.

Tesla: Who knows?

We don't know how many Tesla Model S cars were delivered in April, since Tesla does not report monthly sales like every other automaker.

A rough guess would be 2,250 to 2,500 Model S luxury sedans delivered to buyers during April, a monthly rate derived from its first-quarter sales of "more than 4,750" cars.

If so, that would make the Model S the single best-selling electric car last month--but Tesla won't say, so we can't really tell how well the car is doing.

Tiny battery-electric cars

As for the Mitsubishi i-MiEV, a flurry of sales in January and February that averaged almost 300 cars each month ended in March.

April sales of 127 cars improved on the dismal March number of 31 cars sold, but it remains unclear if the electric minicar will remain above its historic rate of about 50 cars a month.

Finally, either this month or next, the 2013 Smart Electric Drive--the lowest-priced plug-in car in the country--will go on sale, adding to this year's totals as well.

2012 Toyota Prius Plug-In Hybrid - production model

2012 Toyota Prius Plug-In Hybrid - production model

Plug-in hybrids: chugging along

The Toyota Prius Plug-In Hybrid was last year's second best-selling plug-in car, but it's been on a downward trend this year.

In April, just 599 were delivered, for a year-to-date total of 2,952. That's the lowest monthly sales number since the very first month the plug-in Prius went on sale, in March 2012.

The 2014 Honda Accord Plug-In Hybrid logged 55 deliveries in April, more than its total of 45 deliveries in the three months since it went on sale in January. Sales are rising as Honda cautiously rolls out its first-ever plug-in hybrid vehicle in California.

Ford sold almost as many of its pair of Energi plug-in hybrids this month as last, but the mix shifted.

The C-Max Energi fell to 411 from last month's 494, while deliveries of the Fusion Energi rose to 364 from 295 in March.

Compliance cars

Finally, there are the California "compliance cars," those battery-electric vehicles built only in sufficient numbers to satisfy that state's zero-emission vehicle sales mandates.

First to report was the Honda Fit EV, whose 22 deliveries were essentially identical to last month's 23, for a year-to-date total of 68 and a lifetime total of 161 since last July.

After a burst of 133 sales last month for the Toyota RAV4 EV, its numbers fell back to its average levels: during April, 70 of the compact crossovers with Tesla powertrains were delivered.

Ford sold 147 of its Focus Electric hatchback, down on the 180 it sold last month, bringing the total for the first third of the year to an unimpressive 466.

The Chevrolet Spark EV will go on sale in May or June at selected dealers in California and Oregon, and the Fiat 500e will go on sale this summer.


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