The Chevy Volt recorded its second-highest sales month since its December 2010 launch with 1,760 units sold, of which 90 percent were to retail customers. Its all-time high was in March, with 2,289 units sold.

And though GM has said it is “not in a race” with sales against Nissan’s Leaf which was launched the same month – and Nissan’s CEO Carlos Ghosn has recently said he’s not worried over slumping sales at this juncture – the Japanese rival again posted numbers of around one-third the Volt’s, at 535 Leafs sold for June 2012.

Whatever the case, things at the moment are decidedly picking up for the Volt as the Leaf’s sales are still withered, or just holding on. In June 2011, a mere 561 Volts were sold, compared to 1,708 Leafs.

Or sliced another way, the Volt is up by over 300 percent year over year, and last June the still rolling-out Volt and Leaf “race” saw Volt year-to-date deliveries at 2,745 Volts versus 3,875 Leafs – representing 727 more Leafs in June 2011 compared to June 2012. Calendar year to date, Nissan has delivered 3,148 Leafs which is an average rate of around 6,300 per 12 months.

Even so, Nissan has defiantly said it will sell 20,000 Leafs this fiscal year ending in March 2013 considering that Tennessee production begins in December. However, if that’s going to be true, it will need to seriously quicken the pace for the rest of this year, or expect a major blitz at some point.

In contrast, GM stopped saying it will meet a previously specified – and even more ambitious – goal of 45,000 Volts for this calendar year. It has idled the Detroit-Hamtramck plant twice this year to trim supply to match demand. Nonetheless, it’s now in a healthier position, and the company’s mid-year sales of 8,817 Volts already now exceed its 2011 total of 7,671 for the entire year.

Sales for Volts are being helped by word of mouth, more advertising, and California Volts are now eligible for solo HOV lane access. Plus, it has been several months since a protracted spate of negative press set the Volt back to selling just 603 in January. Since then, it has easily topped 1,000 units per month, or specifically February: 1,023, March: 2,289, April: 1,462, May: 1,680, June: 1,760.

The Volt’s sales in June also rose as the aggregate of GM passenger car sales rose by 12 percent year over year.

GM credits its passenger car sales progress to a 32-percent increase in Chevrolet Malibu sales and a 21-percent increase in Buick LaCrosse sales. It also noted combined sales of all seven Chevrolet, Buick, GMC and Cadillac crossovers were up 30 percent versus a year ago.

But it’s all a relative comparison. With just around 3 percent of the total market share being held by all plug-in vehicles compared to mainstream automobiles, the Volt versus Leaf race – or not a race as the case may be – is a microcosm of the big picture.

The big picture for the small market is many wild cards yet remain to be played in months and years ahead. Globally, pressures are spurring demand for these and other electrified vehicles, as their makers continue to race toward technological improvements and work on getting their respective value propositions properly marketed and understood.