Redefining an automotive category -- in the case of the Chevrolet Cruze, that would be the subcompact class -- is a challenge for an automaker, especially when the benchmarks include competitors like the Toyota Corolla and the Honda Civic.

Since its debut, the stately four-door Cruze has been targeted to a dual audience of younger buyers and a middle-aged crowd, said Cristi Landy, marketing director for small cars for Chevrolet. And it's found its target : the nameplate has sold more than 200,000 units in the U.S. as of October, making it GM's hottest-selling car brand, ahead of the Malibu, which sold 181,000 in the same period.

A launch campaign constructed by Goodby, Silverstein & Partners emphasized the Cruze Eco's fuel efficiency -- 40 miles per gallon plus -- and a tagline that it's achieved "by sacrificing nothing." Media spending by the Chevrolet division of GM totaled more that $1.1 billion last year, according to Ad Age data.

"We had to establish a new name, had to get awareness out there and break through against the Civic and Corolla," said Ms. Landy. She readily concedes that initially timing helped propel the Cruze, because of a shortage of Japanese-branded cars affected by the tsunami and earthquake earlier this year, and a rather lukewarm reception to Honda's redesigned bread-and-butter model, the 2012 Civic.

But GM plans to build from here. The woes of its rivals, Ms. Landy said, "definitely gives Chevy an opportunity here to make some noise, and we're going to take advantage of that ."