(FORTUNE Magazine) – What would the America's Cup be without an American finalist? Rough sailing for promoters of the prestigious yacht race. In December the New York Yacht Club, which held the trophy from 1851 until it lost to the Australians in 1983, was sent packing after its boat America II failed to qualify for the semifinals on the seas off Fremantle, Australia. It is still too early to rule out the two remaining U.S. entries, USA and Stars & Stripes, but many sailing fans have given up hope for a rematch between Australia and the U.S. New Zealand's boat, the unexpected winner in the preliminaries, is heavily favored to beat the remaining French and U.S. boats for the right to challenge Australia in late January. A U.S. defeat in the semifinals could reduce the Cup's tourist appeal. The Centre for Applied and Business Research at the University of Western Australia published a study last May predicting tourists would spend $209 million attending the race. Now the organization says that figure may be 20% lower. A poor U.S. showing could have longer-term consequences as well. Corporate sponsors including Newsweek and Ford Motor supplied much of the $7 million to $15 million that each of the six U.S. boats planned to spend. Sponsors may be reluctant to ante up for the next Cup race in the early 1990s even if, as is now proposed, boats are allowed to carry advertising.