Audi has sold cars in the United States for the better part of four decades. It took a while, but Americans have finally caught on to this German luxury brand.

Americans bought more than 100,000 cars from the brand in 2012, the first time that Audi had crossed that threshold in a single year. But that milestone has already receded in the rear-view mirror.

By the end of August, Audi had already crossed that mark and surpassed its U.S. sales total from all of 2012. Its sales are up 14.7 percent so far this year, and that success is breeding confidence.

Audi unveiled two new production cars and two new concept cars earlier this week at the Frankfurt Motor Show, all of which seemed to show that the brand is seeking to double down on its new-found success and design more daring, ambitious vehicles.

Both concept cars were brazen in their appeal to hard-core enthusiasts. The Audi Nanuk Quattro concept is part sports car, part crossover with thick tires and a V10 engine that packs 550 horsepower. The Audi Sport Quattro is a twin-turbo plug-in hybrid concept that, in which the V8 and electric motor combine for a total of 700 horsepower.



"The Sport Quattro, and particularly the Nanuk, broadcast the joy of being a successful car company," said Rich Homan, a Kelley Blue Book analyst. "Audi is having a high-horsepower blast with these concepts, while at the same time affirming the company's place as a performance and technology leader, positioning themselves as the Google of the automobile industry."

Both concepts earned spots in Kelley Blue Book's Top 10 for the Frankfurt show, which is saying something, considering more than 70 new models were unveiled.

With its diesel engine, the Nanuk, an Inuit word meaning "polar bear," is expected to get fuel economy of 30 miles per gallon, which is remarkable given the car's 4,200-pound weight.

"It's emotional, it's interesting," said Dr. Ulrich Hackenberg, Audi's product development director. "It could appeal to someone who has a lot of money, but doesn't live near the best roads."

Of course, Audi's best bet may also be its safest.

The A3 sedan is scheduled to arrive in the U.S. in early 2014, and tap into America's growing interest in smaller cars. Currently, Audi sells the A3 here as a hatchback. In Frankfurt, the brand showcased a new A3 cabriolet that is scheduled to debut in the U.S. in late 2014. It seats four. It will come with a 1.8-liter, four-cylinder engine.

"The A3 embodies so much of what the original A4 embodied, and we're looking to recapture that," Hackenberg said.



In the longer-term plan is to bring the A3 E-tron, unveiled this week, to the United States. The E-tron marks Audi's first foray into the hybrid world, which is a push from once-reluctant parent company Volkswagen to delve into alternate powertrains beyond their entrenched diesel engines.

The E-tron is expected to have a range of 31 miles and receives 101 horsepower from its electric motor and 148 horsepower from its 1.4-liter turbocharged engine.

"It's the first premium car with an alternative drive system for which customers don't have to make any compromises," Hackenberg said.

Pete Bigelow is an associate editor at AOL Autos. He can be reached via email at peter.bigelow@teamaol.com and followed @PeterCBigelow.