If so, it could be bad news for taxpayers who helped bail out GM and now own a third of an automaker that has seen its shares plunge 30% since it went public in 2010.
It could also highlight how much of a political lightning rod GM and the Volt have become since the automaker's federal bailout in 2009 and as the presidential election approaches, analysts said.
"The Volt as a brand has become politicized," said Jeremy Anwyl, vice chairman of auto information company Edmunds.com.
A Reuters report Monday said GM's $39,995 plug-in hybrid was a big money-loser. GM, though, disputed the contention, saying Reuters' research "is grossly wrong" and accusing the news agency of bad math.
The automaker said the news agency incorrectly "allocated product development costs across the number of Volts sold instead of allocating across the lifetime volume of the program, which is how business operates."
The car, which travels about 35 miles on electric power before a gasoline engine kicks in and extends the range an additional 300 miles, has become a political football and favorite target of "GM haters" who are angry over the federal bailout, said Thilo Koslowski, an automotive analyst at research firm Gartner Inc.
That's in part GM's fault because it made the Volt a prime example of why it deserved the federal bailout, he said. More recently, "GM alive, Bin Laden dead" has become a theme of President Obama's reelection campaign.
Plenty of vehicles besides the Volt lose money when their development costs are included in the analysis, analysts said.
Anwyl said he suspects Nissan Motor Co. is losing money on every Leaf electric vehicle it sells because of the investment in battery technology.
Even Honda Motor Co. may lose money on its conventional gasoline engine-equipped Fit because the subcompact has a small profit margin that is eaten up by the unfavorable exchange rate between the Japanese yen and the U.S. dollar, Anwyl said. All of the Fits sold in the U.S. are made in Japan.
"Toyota lost a lot of money in the beginning when it brought the Prius to the world," Koslowski said. "This is particularly true for cars with new powertrain technology like the Volt."
The Prius is now a big seller for Toyota, rivaling conventional family sedans such as Hyundai Motor Co.'s Sonata and Ford Motor Co.'s Fusion in sales. With sales likely to top 200,000 this year, the Prius has become one of the best-selling passenger cars in America.
GM has sold more than 13,000 Volts this year, about half the volume it had expected, and plans to idle the Detroit-Hamtramck assembly plant for four weeks starting later this month.
The automaker, which has spent an estimated $1 billion on the car's development, said that investment into research for battery cells, battery packs, controls, electric motors, regenerative braking and other technologies will be used in many current and future vehicles, "which will help spread costs over a much higher volume."
Although Volt sales are slow, the car is doing better than other new-technology vehicles.
Sales of the Nissan Leaf have fallen steadily since the electric vehicle's launch in late 2010. Nissan sold fewer than 700 of the vehicles in August and just a little more than 4,000 this year.
Whatever money GM is losing on the Volt has not put the company into the red.
GM earned $1.5 billion in the second quarter, and while that was down from $2.5 billion in the same period a year earlier, much of the decline was a result of the recession in Europe rather than Volt sales in the U.S.
Since the bailout, GM has logged 10 consecutive profitable quarters, something it had not accomplished in more than a decade.
Analysts say problems with its European operations are a much bigger threat to the company than whether the Volt program makes money.
Last week, Morgan Stanley analyst Adam Jonas wrote that GM's German-based Opel division has lost $16 billion over the last 12 years and that its losses over the next dozen years could be even greater.
"The unit represents the single biggest threat to GM's long-term financial health and sustainability," Jonas said, recommending that the automaker pursue divesting the Opel division.