Tax rebates in hand, many shoppers returned to stores in May and helped big retailers rebound a bit from a prolonged sales slump.

Some analysts say the rebate-induced jump could extend into the fall, though shoppers are more likely to use their extra cash on necessities than on anything resembling unbridled spending.

Chain-store sales rose 3 percent over last year, the International Council of Shopping Centers said yesterday — a rise that in this limp economy is almost cause for euphoria.

Retail consultant Craig Johnson says the influence of the rebates might even extend through the end of the year. Johnson sees an "ongoing halo effect on retail spending through back-to-school and — unless gas prices reach $5 a gallon" — a continued benefit as people use their rebates to pay off debt and spend more on holiday shopping.

Discounters such as Wal-Mart posted some of the best May sales and will likely continue to fare well, says Stacy Janiak, head of Deloitte's retail practice.

Sales at wholesale clubs such as Costco rose 4.6 percent (minus fuel sales) in May, the shopping centers council said. Drugstores were up 3.2 percent. And discounters' sales jumped 3 percent.

Still, overall, "May came in better than expected," says Michael Niemira, the shopping centers council's chief economist, who predicts a June increase of up to 3 percent.

Some shoppers say they're using rebates to pay bills or to cover higher fuel and food costs.

"This spending spree will likely continue for several months, as only half of rebate checks have been received, and millions of Americans are holding off on major purchases until these checks arrive," says Tracy Mullin, CEO of the National Retail Federation.