DETROIT -- ( TheStreet) -- September auto sales numbers, due out Tuesday, are expected to show that auto sales remain a bright spot in the U.S. economy. And no auto segment is brighter than mid-sized sedans, an area where nearly every major manufacturer has a hot new car. In fact, several cars in the segment are so new that their full impact will not be seen in the September numbers, which are expected to rise about 9% from September 2011 levels, according to Edmunds.com. The seasonally adjusted annual light vehicle sales rate is expected to total 14.4 million, just behind the 14.5 million SAAR in August. September saw "a sharp rebound in consumer sentiment (reflecting) an equity market rally and an improvement in housing, driving a wealth effect" in auto sales," said Jefferies analyst Peter Nesvold, on a Jefferies/Edmunds conference call with auto reporters on Friday. The return of non-primer borrowers provides a tailwind in a market driven by demand for replacement vehicles as the U.S. fleet ages, he said. Strong September pickup sales are expected, fueled by seasonal factors as well as the emerging recovery in housing, Edmunds said. Among mid-sized autos, the cars are so compelling that they are luring traditional buyers of both larger and smaller cars, Edmunds said. "As boomers move to retirement mode, you may see even more people shifting from luxury and full-size," said Edmunds economist Lacey Plache. Meanwhile, compact cars' historic fuel efficiency advantage is being challenged by the fuel efficiency in the mid-sized segment. Referring to a chart listing the nine top cars in the segment, Edmunds analyst Jessica Caldwell noted "there's not a horrible vehicle on this chart," nor are there any aged models. "Sonata, the industry darling for the past few years, is the old man on this chart," Caldwell said. Leading the segment is the new Toyota ( LCC) Camry, which came to market a year ago: sales through August are up 37%. Honda ( LCC) rolled out its new Accord last month, while Nissan just launched the new Altima. So far this year, Camry and Accord are the nation's second and fourth best-selling this year, while Nissan Altima is fifth.