After expending my blood, sweat ant tears all winter, I have eked out a profit of $7,600 playing the horses at Gulfstream Park and Hialeah. This figure was far below my expectations, but it would still be a half-decent return except for one small consideration.

I don't have the money. Uncle Sam does. The Internal Revenue Service has confiscated (or, to use its euphemism, "withheld")nearly $5,000 of my profits, which puts me in a higher tax bracket than Paul Mellon.

And , of course, my plight is mild compared with that of many horse-players. I know one high-roller here who lost a Rolls Royce at Gulfstream but still had the government withhold thousands of dollars of his "winnings."

The 20 percent withholding tax is an inescapably painful fact of life at any track that offers an abundance of gimmick bets that can pay off at big odds. Almost any active horseplayer will hit the few large exactas or triples, even in the course of a losing season, but whenevr he hits the payoff of more than $1,000 for a $2 ticket, the IRS will grab 20 percent of the proceeds.

Even if a gambler invested $1,200 in the ultimate gimmick bet, Gulfstream's Super Six, and wound up with a $1,000 payoff, the IRS would still take the 20 percent.

The IRS assumes that all these big payoffs are won by people who wander into the track, plunk down $2, collect $1,000 or more and then retire for the year. In fact, most horseplayers will lose during the course of a calendar year and will thus have no tax liability. But they will have to wait until April 15, 1982, to claim the money withheld from them, and will probably have to survive an audit to get it back.

In the meantime, their money has been taken out of circulation at the track, which is what distresses the racing industry about the withholding tax. If I had my $5,000 instead of the IRS, I can guarantee that I would be circulating it through the windows at Hialeah and helping the economy of south Florida.

When Ronald Reagan was elected, the racing industry had thought it would have a chance of getting the tax repealed. "The fact that the president loves horses and is conversant with racing has created a glimmer of hope," said Rich Rolapp, director of the American Horse Council. And the administration does seem somewhat sympathetic to the gambling business; a Treasury Department official testified this week on behalf of a bill that would spare legal bookmakers in Las Vegas from paying the 2 percent federal excise tax on wagers on sporting events.

But there is no sign that the administration is going to help horseplayers. In fact, the plight of bettors is likely to get worse.

The IRS recently completed a report, "Study in Compliance for Reporting Gambling Winnings for the Taxable Year 1977," which analyzes the effects of the withholding tax. It says that the tax nets $100 million a year, and suggested that it has made paying taxes much easier and more painless for the gamblers of America.

So to do us a further favor, the IRS now wants to broaden the tax. It recommends that 20 percent be withheld from any racetrack payoff of $600 for $2, as well as lottery and sweepstakes payoffs of $600 or more, and bingo and slot-machine returns of $1,200.

The IRSjustifies the withholding tax, and these increases, on the basis of statistics showing that there has been a greater "compliance" with tax laws since withholding was instituted. This is a bit like saying that muggers achieve a greater rate of compliance when they hold a gun to victim's heads than when they ask them to surrender their wallets voluntarily.