PIERRE, S.D. -- The ethanol groups picking up the tab for $20 vouchers to help tourists pay for ethanol-blended fuel in South Dakota this summer have a limit of 3,000 vouchers.

The problem: More than 10,000 people already have requested vouchers.

"I would be very upset if they issued me a voucher, and then it wasn't accepted because the allotment was up. That is poor promotion," Wayne Allen, a former Mitchell-area resident who now lives in Illinois, told The Argus Leader of Sioux Falls.

"The negative feedback would be counterproductive."

For others, it has little to do with money.

"The $20 is a drop in the bucket," Lawrence Gregory, a dentist from Toledo, Ohio, said. "It's the principle. We've been vacationing in South Dakota for 41 years. Why shouldn't that be worth something?"

The deal targets potential visitors from 10 states -- Colorado, Illinois, Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, Texas and Wisconsin. Those travelers must visit a state Web site and sign up to have the coupon mailed to them.

Once they drive into South Dakota, they can redeem the voucher at a participating station.

With gasoline prices hovering around $3 in some parts of the country, any relief will be welcomed, said Ron Lamberty, for the American Coalition for Ethanol.

The promotion conditions say deal ends Aug. 31 or whenever 3,000 vouchers have been redeemed.