A Senate committee voted almost unanimously yesterday to advance a bill seeking to ban slots-like video gambling machines that have proliferated throughout Maryland, setting the stage for the full Senate to take up the measure today.

The committee acted two days after an opinion issued by Attorney General Douglas F. Gansler's office declared many of the machines around the state illegal.

A sting operation targeting the machines is set for today and tomorrow in St. Mary's County.

Meanwhile, Comptroller Peter Franchot sent e-mails to all state senators yesterday urging them to correct "a huge loophole" in the bill that he said exempts thousands of machines in Baltimore and in Baltimore County that allegedly make illegal payouts.

"There is no logical reason why machines that are cheating the state out of tax revenue and damaging communities in Southern Maryland should still be tolerated in the Baltimore area, or any other part of the state," he wrote.

Speaking to the Senate Budget and Taxation Committee yesterday before it voted to send the bill to the full chamber, Vicki Gruber, chief of staff to Senate President Thomas V. Mike Miller, said the machines in question are already illegal and that the point of the legislation is to prohibit the rest of the devices.

The proposed law also would strengthen the state's position if operators and distributors of the targeted machines decided to sue, Miller told committee members.

"There's going to be litigation ... because so much money is involved," he said.

Miller said the bill is needed because local jurisdictions are deciding on their own whether to allow the machines, many after being on the receiving end of an aggressive push by lobbyists and companies that manufacture or distribute the devices.

Some of the machines are legal under a 2001 ruling by the Court of Appeals because their outcome is not determined randomly, as it is with slot machines. Instead, the results are distributed through a spool of preprinted pull-tabs inside each machine.

Others have proliferated under Maryland's charitable gambling laws, which allows gambling devices if 100 percent of the proceeds go to charity. But lawmakers and state officials have said in recent weeks that the charities are getting only a "pittance" and the attorney general's opinion clearly delineates that many of the machines operating under those provisions have been flouting the law.

The legislation, classifying any machine appearing to provide payouts for a "game of chance" as a slot machine, would outlaw all of them. But it would not eradicated the thousands of video poker machines and other gambling devices at bars and restaurants in Baltimore and in Baltimore County.

A 2006 Abell Foundation report found there were thousands of such machines in the city, and they probably generated $91 million to $182 million a year for operators.

bradley.olson@baltsun.com