The product line has aged, and corporate bosses have been trying to buttress the Buick brand instead.

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Burnett is already a GM agency, handling the GMC truck brand and Buick.

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But Buick survived because of a strong following as a luxury brand in China.

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Buick, though, remains the fastest growing major auto brand in the U.S., according to GM sales data.

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Buick, once coveted for its understated elegance, used to be a dominant brand.

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In the U.S., Buick likely won't approach those numbers because the stodgy image clings to the brand.

WSJ: GM in next phase of hoped for Buick revival

Those models propelled Buick to a 52 percent U.S. sales increase in 2010, the most of any brand.

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