Some new-car shoppers are missing out on hundreds, and possibly thousands of dollars, in extra cash rebates and discounts on top of

already generous incentives being offered by automakers. But there's a catch, according to the Detroit News. You have to belong to a special group of prospects.

One of the most popular offers is aimed at recent college graduates, according to the News. Detroit automakers and several major Asian companies are now offering recent

college grads rebates of $400 to $500 on most models. As an extra sales incentive, General Motors Corp., Ford Motor Co., Toyota Motor Co. and Hyundai Motor Co. also permit recent graduates to defer payments for 90 days, the News said.

By offering sweeter deals to new graduates or military officials, automakers hope to attract new customers and generate loyalty, according to the News. In many cases, the deals are regional, which means not every dealer in every part of the country is offering them, the News said.

While the automakers do publicize the graduate and military rebates, dealers say many customers are not aware they may be eligible for additional savings. But there's evidence

vehicle shoppers are not shy about doing battle with sales personnel to get a fair price, according to the News.

"People don't care where the deal comes from; they expect at least a $3,800 discount from the sticker -- the highest level it's ever been," said Art Spinella, director of CNW Marketing Research, Inc., in Bandon, Ore.