A revolution is starting to sweep the thoroughbred racing world.

It is so profound that it may, in one bold stroke, revitalize an industry whose business has been declining ominously in the last few years.

It is tinged with irony, because the salvation of racing may be precisely what many people within the industry took to be its curse: gimmick betting.

But since Hollywood Park in Inglewood, Calif., introduced a form of gimmick betting called the Pick Six, even the most skeptical and reactionary racing officials acknowledge that its results have been spectacular.

Hollywood's customers have been betting an average of $429,000 a day on the Pick Six over the last two months. The track's attendance has skyrocketed, up 28 percent over last year, and the overall betting has risen 25 percent.

Seeing these figures, tracks across the country have been scrambling to start their own Pick Six wagering. Chicago's Arlington Park introduced the gimmick this week. Monmouth Park and Atlantic City Race Track will follow suit later this month. Maryland will probably have the Pick Six by the fall.

The reason for the gimmick's enormous popularity is obvious: greed. The object of the Pick Six, as the name implies, is to pick the winners of six consecutive races -- at Hollywood Park, the second through the seventh. Because of the difficulty of this task the payoffs are often astronomical.

In mid-May, the owner of a hot dog stand won $305,668 at Hollywood. His record was eclipsed a week ago when a doctor won $375,897. And that record is not expected to last long.

The concept of the Pick Six is hardly new; Caliente Race Track in Mexico has been luring Californians south of the border for years with the promise of enormous payoffs. But the current impetus for the Pick Six was provided by the installation of computerized ticket-selling equipment at Hollywood and most other major tracks across the country. The equipment made betting six races on a single ticket technologically feasible.

Vernon Underwood, Hollywood's chairman of the board, had seen a version of the Pick Six operating successfully in Europe. Because of his enthusiasm, the track asked permission of the California Racing Board to try the gimmick. Hollywood overcame stiff opposition from the holier-than-thou pursists at the state's other major track, Santa Anita, and set up the ground rules for the Pick Six.

Players mark their selections for each of the six races in pencil on a special card, which can then be pushed through a scanner that records all the bets. If a player makes two selections in each race that is a total of 64 different combinations, costing $128, but the computer records them all instantaneously.

Seventy-five percent of the money in the Pick Six pool is distributed among the people who select the larest number of winners (which usually is six). Twenty-five percent of the pool goes as a consolation prize to people who pick the second-largest number of winners (usually five).

One of the popular arguments against gimmick wagers -- that they cause corruption -- obviously doesn't apply to the Pick Six. Even if sinister fixers did manage to insure that a couple of favorites were going to lose in the Pick Six, they would still have to spend several million dollars to tie up all the remaining possible combinations.

But a more persuasive argument against the Pick Six is the one Santa Anita officials presented to the California Racing Board. They maintained that gimmick bets with large payoffs take too much money out of circulation and thus have a negative impact on a track's business.

If 3,000 people at a track hit a $100 payoff, they go right back to the windows and keep that money recirculating through the parimutuel machines. But if one man cashes a $300,000 ticket, the track will see little of that money again.

This argument sounds logical, but in the case of the Pick Six it has proved wrong. On the contrary, the Pick Six has succeeded in luring fresh money to the track.

It has excited not only regular horseplayers who want to employ their handicapping skills to make a fortune, but also people who would otherwise be playing a lottery.

Hollywod operates "early-bird" betting windows that open before regular racing hours, and average $90,000 a day in Pick Six business at these windows. "Most of that is new blood," a Hollywood official said. "A lot of people come and turn in 15 or 20 $2 cards as if they're bringing them for everybody at the office.

Most of these people are probably playing hunches or lucky numbers.But the day will come when they are moved to pick up a copy of the Daily Racing Form and try to apply a little logic to their selections. Every time that happens, a new horseplayer will be born.