Chevrolet is taking the point as General Motors Corp. struggles to buff up its green image—dull compared with rivals such as Toyota Motor Corp., and tarnished from the earlier, abruptly ended EV1 electric car.

The stakes this time around are larger than ever for GM, whose vehicles over the last century have burned up a veritable sea of fossil fuel.

Ed Peper, Chevrolet general manager, insisted the green streak is a permanent part of Chevy. "This is not something that's an ad campaign for a while; it's something that's core to our brand," he said.

GM was ahead of the curve in 1996 when it introduced the EV1, the first all-electric car marketed by a major automaker. The debut commercial from Publicis & Hal Riney, San Francisco, showed fans, boom boxes, mixers and toasters breaking away from the house to arrive at the family garage to greet the new car. The ad proclaimed: "The electric car is here—EV1, General Motors." But the car, offered through Saturn dealers in limited numbers, had a range of only 70 miles, and the EV1 never took off. GM pulled the plug on it in 2000.

As far as the current popularity of gasoline-electric hybrids, GM Vice Chairman Bob Lutz acknowledged in published reports last March that GM could have come out with similar technology at the same time that Toyota unveiled the Prius, but didn't. Instead, GM focused heavily on profitable trucks and sport-utility vehicles as that segment got hot in the 1990s and ignored its small-car lineup.

Now playing catch-up, GM is spending freely to support Chevrolet's high-profile "Gas-Friendly to Gas-Free" campaign. Chevy agency Campbell-Ewald, Warren, Mich., kicked off the effort at the worldwide Live Earth concert event in July 2007.

Campbell-Ewald, as part of the "Gas-Friendly" campaign, has created some early TV advertising for the Chevy Volt, a plug-in hybrid, even though GM doesn't expect to deliver the new car until 2010. The Volt, which can be charged from any electrical outlet, still faces some technological hurdles. The car uses lithium ion batteries, similar to the batteries found in laptop computers, and in rare instances or if they're damaged, the batteries can experience a chain reaction that causes them to burn up.

Skirts hybrid-leader Toyota

GM wants to promote its agenda on fuel efficiency, and it believes hybrids alone aren't the only answer to oil dependence. GM argues that reducing the need for foreign oil in the long run will require many alternatives. The range-of-options agenda is partly common sense and partly self-serving for GM, since Toyota is perceived as the leader in hybrids. At the same time, GM wants credit for making major investments in fuel cells.

The goal is to create mass-market consumer demand to make these technologies financially viable. That's part of the rationale for tapping Chevrolet, GM's largest division, as the lead brand.

"It's significant that it's the Chevy brand doing this. We're the big-volume brand," Mr. Peper said. "We're not a niche brand that's going to pump out a few image cars to showcase that we're quote-unquote 'green.' We think this is the way to have a significant impact and really reduce our dependence on oil."