NEW YORK (AP) -- Even before Harry Potter makes his movie debut, the bookish boy wizard is working magic on retailers.

Merchandise tied to Warner Bros.' "Harry Potter and the Sorcerer's Stone," which hits theaters Nov. 16, has been available in stores for weeks, and merchants including Toys R Us and Kmart have been pressed to keep up with demand.

Hot sales of Harry Potter games, puzzles, trading cards and other items are delighting stores that were looking ahead to a bleak holiday shopping season.

"It's almost as if a light switch went on," said Jim Silver, publisher of The Toy Book, an industry monthly. "It looks like the product has legs and will be a strong seller for the holidays."

Harry Potter merchandise is expected to reignite the licensing industry, which soured last year with slumping sales of the once-hot Pokemon and Star Wars merchandise. Under a license, a manufacturer has permission to market products using a name, logo or image.

The licensing business is also expected to be helped by sales of merchandise tied to other films due out this holiday season: Disney Pixar's "Monsters Inc." and New Line Cinema's "Lord of the Rings."

Toymakers, meanwhile, also have their hopes high. Mattel Inc. is the master licensee, or biggest supplier, of Harry Potter toys, while Hasbro Inc. has the master toy license for Monsters Inc. and Toy Biz is the main licensee for "Lord of the Rings."

Mattel expects that certain items -- particularly its Levitating Challenge game, Roaring Snorin' Norbert (an interactive dragon), Snape's Potions Lab and a Hogwart's Castle playset -- to sell out by Thanksgiving.

And Lego Systems Inc. decided to increase production within the past week of toys including Hogwart's Express train and Hogwart's Castle to keep pace with retailers' reorders.

"This could really help matters, and the sooner it happens, the better it will be," said David Miller, president of the Toy Industry Association, who expects holiday toy sales to be up 2 percent to 4 percent from last year, when sales were unchanged from the 1999 holiday season.

Silver, the Toy Book publisher, believes Harry Potter merchandise could generate sales of several hundred million dollars in one year. Warner Bros. officials declined to comment on projections.

However, toy analysts are mindful that the economic and political uncertainty that followed Sept. 11 could limit the success of Harry Potter products. "Parents could pull back on spending, including toys," said Chris Byrne, an independent toy consultant.

But Warner Bros. officials are betting that the magical story will be a great comfort to children and adults as well. The movie, based on the first of author J.K. Rowling's best-selling series, follows the adventures of Harry, an orphan boy who is invited to become a student at the Hogwart's School of Witchcraft and Wizardry.

"My sense is that this is such great family entertainment, and I think that everyone is looking foward to seeing this film," said Dan Romanelli, president of Warner Bros. worldwide consumer products.

"We have kids who were big fans of the book, so there is a lot of anticipation for the movie," said Susan McLaughlin, a spokeswoman for Toys R Us, whose biggest hits have included Mattel's action figures and Potions Lab.

The strong reception for the movie-related products contrasts with the mixed response last year for the limited offerings tied to Rowling's first book. Mattel's Trivia game did well, but decorative items like figurines did not. The lackluster sales prompted retailers, burned two years ago by the saturation of Star Wars products, to cautiously order merchandise connected to the movie, Silver said.

Romanelli said he had always anticipated that once the buzz started with the film, it would create demand for Harry Potter merchandise. Now, he said, "the big challenge is meeting the demand."

However, mindful of the Star Wars licensing overkill, Warner Bros., with author Rowling's approval, limited the number of companies with licenses. There are fewer than 90 U.S. licensing partners, compared to about 200 for movies like "Batman." Other licensees include Hasbro, Hallmark and Totes.

Only about several hundred products are being released, compared with more than a thousand that Warner Bros. does for a typical blockbuster, Romanelli said. The studio also decided against Harry Potter promotions in fast-food restaurants.