One year from now some 500,000 shares of a Maryland racetrack should come up for sale; the estimated price of $4 million to be paid to the United States Treasury.

That sale will represent the first example of a new kind of punishment for drug dealers, businessmen, gangsters or politicians convicted on racketeering charges. Besides serving time in jail and paying fines, these crimiinals can now be forced to forfeit the ill-gotten gains of their corruption.

In the Marvin Mandel racketeering case, the first in which the 1972 law fully applies, the property to be forfeited is shares in Bowie Race Course.

"This should take the profit out of corruption, really put a bite in the law," said Assistant U.S. Attorney Daniel J. Hurson, one of the prosecutors in the Mandel trial. "It could mean devastating losses to corrupt businessmen, far worse than a jail sentence."

At the sentencing Friday of Mandeland his five codefendants on political corruption charges. U.S. District Judge Robert L. Taylor signed an order requiring the race track stock to be turned over to the federal government within 30 days. The government must sell the property confiscated under the law, but only after the appeal process has been exhausted.

Some half-dozen appeals have been filed solely on this question since the six men were convicted on Aug. 23. This is testimony, said one attorney, to the seriousness with which the men view the loss of their property.

"It truly does add a whole new dimension," said Mandel's attorney, Arnold M. Weiner. "It is the same as going from tic-tac-toe to three dimensional tic-tac-toe. The whole game is changed."

One lawyer familiar with the case said that some of the convicted men could face a few years in prison more easily than the prospect of losing major investments.

The appeals did pay off. Judge Taylor acquitted the men on one racketeering count, allowing three of them to retain an asset worth $800,000 to each.

The loss of their racetrack stock will not cause the financial ruin of convicted defendants Harry W. Rodgers III, W. Dale Hess, William A. Rodgers and Irvin Kovens, who are all millionaires. But it will sting, according to one defense attorney who disagrees with the application of the law to political corruption cases.

"That law was passed when everyone was running around saying the Mafia is taking over General Motors. It was meant to stop gangsters from using legitimate business for organized crime. Nobody was talking about using it in white-collar crime or political corruption cases," said William G. Hundley, attorney for Hess.

But like most areas of crime and punishment, the orgins of this law go back much further than 1972, when Hundley himself testified before Congress in favor of enacting the measure.

The government's right to force forfeiture of property in certain criminal cases was accepted in this country until 1790, when it was abolished by Congress. It was only resurrected five years ago as an answer to what Congress perceived as the growing threat of organized crime.

The racetrack stock that the government will confiscate, if the appeals are denied, covers shares in one of three major racetracks in Maryland, the Bowie Race Course in Prince George's County.

The corruption scheme for which Mandel and his codefendants were convicted covered a six-year period of favors passed between Mandel and his friends. The governor received $350,000 worth of gifts. In return, he manipulated the laws and lawmakers of Maryland so that his friends' interest in the dilapidated, half-mile Marlboro Race Track could be parlayed into an interest in the Bowie Race Course. The men made a $1 million profit through the merger and closed down the Marlboro track in 1973.

With more to lose, reasoned prosecutor Hurson, there may be less likelihood that wealthy businessmen would want to use their property to corrupt politicians even if it may mean greater profits.