Racing executive Joseph A. De Francis could receive millions of dollars in slot machine profits every year for two decades even if he sells his minority interest in Pimlico and Laurel racetracks, a government document shows.

The disclosure brought an angry reaction from a leading legislator and prompted speculation in Annapolis that Gov.-elect Robert L. Ehrlich Jr.'s proposal to allow slots at Maryland tracks could face tougher opposition than expected.

"Those opponents of slot machines like me are going to use this to hammer the hell out of it," said Sen. Thomas M. Middleton, a Charles County Democrat and the incoming chairman of the Finance Committee.

Details of the contract under which De Francis and his sister, Karin, sold their majority stake in the Maryland Jockey Club -- parent of the two tracks -- were spelled out in a filing with the Securities and Exchange Commission this week.

One member of the Maryland Racing Commission, who spoke on the condition of anonymity, said he's worried that there won't be enough revenue from slot machines to meet all the demands being placed on the expected windfall.

"The principles of mathematics don't apply," the commissioner said.

The SEC filing by Magna Entertainment Co. shows that in addition to being paid for selling their majority interest in the two racetracks, the De Francises received $18.4 million from the Ontario-based company for an option to buy their remaining 49 percent stake in 2006-2007.

Magna could exercise that option by paying them another $18.3 million.

The agreement goes on to set up a subsidiary called Maryland Ventures, a company designed to receive the proceeds from any slot machines the state might permit at the tracks.

The agreement calls for 65 percent of the pretax earnings of Maryland Ventures to go to the De Francises and former minority owners for the first five years of slot machine operations. That percentage would decline to 50 percent after five years and 40 percent after 10.

The payments to the De Francises would stop after the slot machines had been at the tracks for 20 years.

In an apparent attempt to clarify the arrangement, Magna released a statement by De Francis yesterday in which he said he and his sister would be entitled to an average of 18 percent -- not 49 percent -- of any profits from "alternative gaming" at the tracks.

The payments to Joseph De Francis -- chief executive officer of the Jockey Club and a polarizing figure in Annapolis -- would range from 12 percent in the first five years of slot machine operations to 7 percent in the final 10.

Karin De Francis, a senior vice president, would receive slightly more. Leucadia Corp., which was a former investor in the club, former minority owners of Laurel, and former general counsel Martin Jacobs would also receive percentages.

How much that could mean in actual dollars is difficult to gauge.

Jeff Hooke, an investment banker who advocates selling licenses for any slot machines at a high price, estimated that profits from slots at Pimlico and Laurel could come to $290 million in the early years and could grow.

Hooke, chairman of the nonprofit Project $1.5 Billion Recovery, said that could result in a payout to De Francis of about $30 million a year for 20 years -- with growing business offsetting his declining percentage.

Supporters of slots have said Hooke's earnings projections are wildly inflated. De Francis declined to discuss potential earnings, and referred to his prepared statement.

The statement said the net income would include only money left over after operating expenses, the capital costs of installing slots, state gambling taxes and a share for the thoroughbred industry.

By some estimates, simply operating the machines and the facilities in which they would be placed would take up to 35 percent of their revenue.

The state would need another 50 percent to 60 percent to balance its budget and to raise promised revenue for education, according to the racing commissioner who spoke to The Sun. That would leave just 5 percent to 15 percent for racing purses, current and past track owners, improved facilities and a fund to encourage Maryland's horse breeding.

The racing industry has said it needs money from slots to make purses -- the money paid to the owners of top-finishing horses -- competitive with neighboring states. Providing a profit to the track's previous owners would dilute the money and would likely be the subject of lively negotiations with lawmakers.

"If we say yes to them, how can we say no to nonprofit entities like the Waldorf Jaycees?" Senator Middleton asked.

Hoffberger, president of the Maryland Thoroughbred Horsemen's Association, said he doesn't blame De Francis for driving a hard bargain in the negotiations.

Hoffberger is concerned that a windfall for the De Francises may prove unpopular with lawmakers, possibly sapping support from slot machine legislation.

"The slot legislation is not going to be easy and anything that anyone sees as a negative isn't going to help," Hoffberger said. "The tracks are going to have to explain their deal."