DETROIT (Bloomberg) -- At his Houston Cadillac store last weekend, Carl Sewell had an unusual experience: He helped a mother secure a baby seat into a car she was considering. Young-shopper sightings were once a rarity for Sewell.
"It's a pretty diverse group that's coming through the door now," said Sewell, who owns four Cadillac dealerships in Texas. "The new ATS is bringing in the ideal buyer: younger and better educated."
Cadillac's $33,095 ATS sport sedan drove a 49 percent rise in sales last month for General Motors' luxury line, outpacing a forecast from researcher Edmunds.com that the brand's deliveries would grow by 37 percent.
It was the sixth consecutive month of gains for Cadillac, which is rolling out 10 new models by 2015 and building on buzz it earned at the New York auto show for the debut of the stylish redesign of its CTS sedan.
"Cadillac's performance certainly exceeded expectations, and the ATS was the driving factor," said Jeff Schuster, auto analyst with LMC Automotive in Troy, Mich. "They have a lot happening with their lineup and the vehicles are hitting with consumers."
Cadillac's strong showing came as U.S. automakers rode a newfound success in sedans to their best monthly sales in more than five years. With Detroit's best car lineup in decades, GM's March sales rose 6.4 percent; Ford Motor Co. gained 5.7 percent on the strength of a record month for its Fusion family car; and Chrysler Group jumped 5 percent.
"Cadillac is doing well," said Christian Mayes, a St. Louis-based analyst with Edward Jones & Co. "They're in the process of refreshing the brand and that gets some more interest."
Cadillac's success is critical to GM CEO Dan Akerson's goal to boost operating profit margins in North America to 10 percent by mid-decade, from 7.4 percent over the last three years.
"Cadillac makes more money than our average portfolio," Chuck Stevens, GM chief financial officer for North America, said last month during a forum in New York. "As we continue to fill out the lineup in the portfolio and grow Cadillac, that's going to have a net benefit from a margin perspective."
The ATS, introduced last year, is aimed at changing perceptions about Cadillac. Engineered to take hot laps on Germany's Nuerburgring race course, the small sports sedan is marketed with frenetic ads showing young drivers speeding down a mountain road in Morocco or other exotic locales.
Consumer Reports magazine praised the ATS in its May issue, saying its "impeccable fit and finish is among the best we've seen from GM" while the vehicle's "sharp handling, eager performance and responsive steering give up nothing to the best European sports sedans." It was named North American Car of the Year by a jury of journalists at this year's Detroit auto show.