Scott Wine, chief executive of Polaris, said that for many people in middle America, off-road vehicles used for work and play offer a type of entertainment that can be less expensive than taking long trips or joining a golf club. His company's sales in the quarter rose 25 percent to $1.1 billion and continued to be strong in early October despite the temporary federal government shutdown, Wine said.

"We're optimistic about the rest of the year, and we're expecting to do well in '14," he said in an interview. Polaris's profit in the quarter rose to $113.1 million, or $1.59 a share, up from $94.3 million, or $1.33 a share.

Higher-income Americans "are finally beginning to start spending again," said James Hardiman, an analyst at Longbow Research in Cleveland. He estimates that retail sales of leisure boats made by Brunswick (BC), Lake Forest, Ill., were up nearly 10 percent in the third quarter. Brunswick is due to report results Thursday.

Likewise, Milwaukee-based Harley, which posted a 21 percent rise in third-quarter profit, cited strong demand for its 2014 line of motorcycles introduced in August. Harley has been expanding sales to younger riders, women and minorities, adding to its core fan base among white male baby boomers.

"We're cautiously optimistic about the [U.S.] economy," said Keith Wandell, Harley's CEO. The company increased its financing for subprime borrowers but said it was being prudent. Revenue, including motorcycle sales and financing, increased 7.5 percent to $1.34 billion.

Retail sales of Harley motorcycles were up 20 percent in the U.S. and 6.5 percent elsewhere. Part of the U.S. gain reflected greater availability of Harley motorcycles in the latest quarter compared with a year earlier, when a software installation disrupted production. But Harley officials said strong sales of new models were a bigger factor. The company says its new Rushmore series offers better brakes, making it easier for novice riders to control the motorcycles, and an improved cooling system to divert exhaust heat from riders' legs.

Despite Harley's rapid sales growth in the latest quarter, its U.S. retail sales for the full year still are likely to be about 35 percent below their 2006 peak, Longbow's Hardiman said.

At Winnebago, based in Forest City, Iowa, sales in its fiscal fourth quarter ended Aug. 31 were up 32 percent from a year earlier. "We knocked it out of the park in the fourth quarter," Winnebago's chief executive officer, Randy Potts, told analysts last week when the company reported results.

Frank Morgan, sales manager at family owned Hufnagel & Majors Inc., which sells recreational vehicles including Winnebagos and other travel trailers, said business began picking up in the summer. "I think people feel a little more secure," said Morgan. Interest rates are low and banks more willing to lend, he said. He also said the growing natural gas industry in western Pennsylvania's rich shale deposits has boosted jobs and strengthened the local economy, making customers at the Harmony, Pa. based dealership feel more comfortable about spending.

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"You don't hear people talking about the price of [gasoline] anymore," he said, which indicates a level of security. His average customers spends about $15,000 to $25,000, he said.

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