Around the country, ballot measures to allow slot machines or casinos usually fail, according to experts who study the issue.
Gov. Martin O'Malley said this week that he was "inclined" to put the issue of legalizing slot machine gambling on the next statewide ballot for voters to decide.
But experts say such measures are difficult to sell to voters, typically generating intense grass-roots opposition and only lukewarm support.
"These are easier to defeat than they are to win," said William R. Eadington, director of the Institute for the Study of Gambling and Commercial Gaming at the University of Nevada, Reno.
He said it is easy to "demonize gambling in general - you can make very emotional, visceral appeals to voters."
I. Nelson Rose, a Whittier Law School professor and authority on gambling law, agreed that few voters strongly support legalizing slots or casino-style gambling - other than those who have an economic self-interest in the proposals. But strong and vocal opposition to gambling initiatives comes from people on both ends of the political spectrum, although for different reasons.
"If you have to put it to a vote of the people, there is a significant chance it will be defeated," Rose said. "If the legislature really wants it, it will do what Pennsylvania did and just pass legislation to put them in."
Other states in the region - West Virginia, Pennsylvania, Delaware and New York - legalized slots and racetrack casinos through votes of their respective legislatures, he said. None were put to a statewide vote, he said. Voters in many states have, however, approved lotteries and pari-mutuel wagering over the objections of gambling opponents.
O'Malley, who campaigned on a pledge for "limited" slots at racetracks, has recently floated the idea of placing a constitutional amendment to allow slots on the November 2008 ballot as he seeks to build a consensus for his plan to close Maryland's $1.7 billion budget gap.
He has called a special session for Oct. 29.
Del. Shane Pendergrass, a Howard County Democrat, said yesterday that she asked for a bill to be drafted that would put the slots issue before voters in November 2008.
Her bill would give voters one "yes" or "no" choice on legalizing slots. The measure would have to pass statewide, and slots could go only to those counties where more than 50 percent of the voters approved.
"This bill has a chance to get through the House," Pendergrass said. "It seems to me it's a way of moving the issue forward."
Eadington suggested that gambling interests in neighboring states, threatened by the potential competition, might put up money behind the scenes to help keep slots out of Maryland.
Casper R. Taylor Jr., a former speaker of the House of Delegates who is now a lobbyist, also predicted gambling interests from Delaware, West Virginia and Pennsylvania would "spend enormous amounts of money" to influence any election on slots in Maryland.
"Somewhere around $500 million in Maryland money that is going into their states is at risk," Taylor said. "If they could maintain the status quo, they'd be tickled pink."
Thomas A. Grey of the National Coalition Against Legalized Gambling said he would prefer that Maryland lawmakers reject slots outright. But he said he's confident that anti-gambling forces could win if the issue goes on a statewide ballot.
"It's at the grass-roots level where we win," Grey said. "Their money is neutralized and it sometimes works against them. In Madison, Wis., they spent $1.4 million to our $45,000 and we beat them 63 percent to 37 percent."
Senate President Thomas V. Mike Miller said he didn't think O'Malley was trying to kill slots by suggesting the referendum.
"From the governor's point of view, if Republicans are not going to participate and help the governor pass any part of his plan, the governor has to negotiate only with Democrats, including those who have voted against a slots plan in the past," the Southern Maryland Democrat said.
But Miller said O'Malley's efforts to use a ballot issue to broker a budget deal should have been his last resort, only if the votes for a slots bill couldn't be nailed down.
House Speaker Michael E. Busch said there's "more of an openness" among legislators for putting the issue on the ballot than for voting for a slots bill.
A constitutional amendment would restrict the sites and number of machines, Busch said.
Asked if a statewide issue would resolve the slots debate, Busch said it could.
"If people vote no, then they didn't want it. That's pretty easy," the Anne Arundel Democrat said.
The governor has not decided whether to ask legislators to put the slots issue on the ballot, said O'Malley spokesman Rick Abbruzzese. It's "too early" to say whether O'Malley would campaign in favor of a constitutional amendment legalizing slots, Abbruzzese added.
Aaron Meisner, chairman of Stop Slots Maryland Now, said a referendum won't relieve the "fatigue" that legislators and Marylanders have with the slots debate.
"The worst part is if the referendum is defeated, Magna and Penn National and all of those other companies will be back in Annapolis the very following January to talk about the same thing all over again," he said.
Still, a referendum would give O'Malley and legislators "an escape route from what looks to be a very controversial issue," said Matthew A. Crenson, a political science professor at the Johns Hopkins University.
The idea of letting voters decide is "a hard argument to resist and I think one that is going to prevail in the end, especially if it has provisions to allow counties or cities to opt out."
If the issue does go before voters, Crenson said, "The gaming industry is going to descend on Maryland like locusts. But [for] the people who don't want slots, no amount of advertising is going to persuade them. Others are likely to say 'Yes, but not in my backyard.'"
email@example.comSun reporter James Drew contributed to this article.