Chevrolet used television broadcasts of the Summer Olympics over the weekend to advertise a new car so fuel efficient, its average owner could drive it through a typical day without using a single drop of gasoline. Interested? There's only one problem. The car won't reach showrooms until 2010, if it reaches them at all.

General Motors is running a series of advertisements during the games that feature brief mentions, and sometimes brief glimpses, of its upcoming Chevy Volt plug-in hybrid vehicle. The Volt, its engineers claim, will be able to travel at highway speeds for up to 40 miles on electric power alone -- meaning that for many owners, its electric engine would rarely be used.

explains, 'One such spot ends rather incongruously with a long look at the Volt concept vehicle and its planned 2010 introduction date.' Chevy advertising director Kim Kosak told Edmunds, 'We wanted Volt to be an important punctuation to the spot. It's the first where we've brought to the market this clearly.'

Brought the Volt to market? Not exactly. An Atlantic Monthly article probing deeply into the Volt development project recently left the impression that GM may miss its target production date for the car, though GM hopes to have the first production Volt ready for its 100th anniversary celebration later this year. As far as anyone outside GM knows, there is no Chevy Volt yet. GM says it has tested parts of the proposed powertrain for the Volt in the body of a last-generation Chevy Malibu, but has not let journalists see that supposed test car. The company says the chassis for the Volt is still under development, and will be used on several 2010 cars. The General has shown the proposed body of the Volt as a concept at car shows. But the Volt's chassis, body and powertrain have never been put together and tested.

If it does come to market, no one is clear on how much it will cost.

(the magazine of the Institute of Electrical and Electronics Engineers) explains, 'Not since the earliest days of the industry tried to develop a new body and chassis and a new energy storage and power delivery system, all at the same time and all for the same car.' The challenge is so unique that it's very difficult for anyone to predict whether GM will be able to pull it off in the timeframe the company has set for the project.

But the ads are working.

notes that, after the commercial aired, the Volt 'skyrocketed to the #11 search overall in Google Trends.' for the day of the first ad shows the jump, but we should note, the term has dropped out of the top 100 today.

The Volt has increased its presence on our cultural radar screen enough to get a mention from presidential candidates now. notes both John McCain and Barack Obama have mentioned the vehicle in recent remarks.

Now, all GM needs to do is actually build one.

To see the highly-anticipated Chevy Volt for yourself, see our gallery. To read more about what the auto press is saying, see the U.S. News preview of the 2010 Chevy Volt.

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