Virginia's House of Delegates urged Maryland lawmakers today to keep slot machines away from the Potomac River, where the presence of riverboats or shoreline casinos might allow the ills of legalized gambling to cross over into the commonwealth.

House members voted 90 to 7 to approve a resolution by Del. Robert G. Marshall (R-Prince William) that notes the "potential for abuse and criminal activity" from gambling and calls on Maryland officials to "refrain from authorizing . . . gambling in or on the shores of the Potomac River."

Maryland Gov. Robert L. Ehrlich Jr. (R) has proposed allowing slot machines at four horse racetracks, a move that would launch the state into the big leagues of gambling. He would use some proceeds from the gambling operations to help close a $1.8 billion budget shortfall.

Other Maryland lawmakers have discussed going further, allowing resort casinos or riverboat gambling. The proposals are being debated during Maryland's General Assembly session, which ends April 7.

The possibility of gambling on their state's borders has spooked some in Virginia, who recall the state's involvement with gambling off the shores of Colonial Beach and elsewhere in the late 1940s and '50s. During that time, gambling was allowed up and down the river, which is part of Maryland. Marshall said there were gambling rooms on "attic boats" off Alexandria's shore, a barge with slot machines off Prince William County's coast near Leesylvania Park and more than 1,000 slot machines on the river near Colonial Beach.

In the mid-1990s, a Virginia proposal to allow riverboat gambling to return was killed. Marshall said he believes Ehrlich's proposal, which calls for slot machines at only the four racetracks, could evolve beyond that.

"This will slide south, from Annapolis to Richmond," Marshall predicted. If slots are successful in Maryland, he said, there will be a similar push to allow them in Virginia. "Some people want it here, and they will look at what's going on in Annapolis as a green light to start lobbying here."

Ehrlich's slot proposal is designed to generate about $1 billion a year for the cash-starved state by requiring one-time licensing fees and dedicating most of the annual profits to education. The assembly is debating whether -- and how -- to distribute those funds.

Ehrlich spokesman Paul Schurick said politicians in Pennsylvania and Delaware also have expressed their concern about gambling to Ehrlich. In all three cases, the political leadership understands that they represent constituents who want to gamble. For different reasons, they believe expanding gaming in Maryland would hurt their economies, Schurick said.

Supporters of gambling in Virginia say Ehrlich's proposal gives them hope that slot machines may come to Virginia. Charles Davis, a lobbyist who has represented the nation's largest slot machine manufacturer and the Harrah's casino, said Marshall's resolution was misplaced.

"I would think that elected officials in Maryland would not be any more receptive or pleased to this resolution from Virginia than this General Assembly would be to a resolution offered up by Maryland," he said. He said Virginia lawmakers should take Ehrlich's cue and examine the financial benefits of allowing slot machines, perhaps at the state's only racetrack, Colonial Downs.

"Virginia is not preventing people from partaking of gaming activities," Davis said. "It is simply losing millions of dollars in revenue by not allowing it to take place here. I can't recall the last time I saw someone with a gun to his head being forced to go to Atlantic City or Las Vegas."

A spokeswoman for Virginia Gov. Mark R. Warner (D) said he is supportive of the House resolution and opposes any action in Maryland that would give Virginians direct access to gambling on the Potomac.

"We believe that Virginians should decide whether Virginians have slot machines," spokeswoman Ellen Qualls said. "We would hope to not see any that were accessible from Virginia shores."

Marshall said he may travel to Annapolis to present the Virginia resolution and testify against Ehrlich's slot proposal in the Maryland assembly. His argument: "They get the money, we get the problems."