Voters in Anne Arundel County are nearly evenly split on a ballot referendum that will decide the fate of a planned billion-dollar slots casino and entertainment complex at Arundel Mills mall, according to a new Baltimore Sun poll.

Forty-seven percent of likely county voters said they would support Question A, the ballot question that would allow zoning needed to build a slots parlor at Arundel Mills, and 45 percent said they are opposed. Because the survey has a margin of error of 5 percentage points, the results represent a statistical tie.

"It's a toss-up," said pollster Steve Raabe, president of OpinionWorks, the polling company retained by The Sun.

Eight percent of those polled said they were undecided — a group that in coming days will be the target of a huge advertising campaign that pits two deep-pocketed groups against each other.

Baltimore-based Cordish Cos., which has a license to build the slots parlor at the mall, is lobbying heavily for the zoning measure, while the Maryland Jockey Club and related interests are fighting against it, hoping to steer the project to the Laurel Park race course.

The ballot question addresses only the zoning issue, and its rejection would not mean that the slots project automatically goes to the racetrack. Still, many county voters said they prefer the gambling project to be built at a horse racing facility.

When asked their views on the most appropriate venue for slots, regardless of their position on Question A, nearly four in 10 voters said a racetrack would be the best location.

Twenty-seven percent of respondents said the mall, and 10 percent said either they didn't care or said either location is acceptable. Eighteen percent said they didn't want slots at all, and 7 percent said they were unsure.

Some undecided Arundel residents said in interviews they had been paying attention to the bombardment of television ads, but have not been swayed yet.

Romona Curry, a 56-year-old retired federal worker from Glen Burnie, said she's undecided but "leaning closer" to supporting Question A.

"At first the ads that went out talked about that the slots would be inside the mall, that was the indication, and I didn't want that," said Curry, who doesn't gamble. "But when they started talking about it would be in a separate building … and they're not mingling with the mall people, then I'm more for it."

Charles Johnson, a computer programmer, said he's in favor of slots in the state, but is torn over the location. He plans to "read up on the issue" in the coming days before deciding how he'll vote.

"That was the purpose of the original bill, to save the [horse racing] industry," said Johnson, 63, a Gambrills resident. "And I think we should stay with that. However, I'm in favor of us raising revenues with slots. I believe that the tracks are the best place. But what I can't figure out is, if we don't put them at Arundel Mills, does that mean us not having them at all, and the revenues would continue to stream out of the state?"

Support for the referendum varies within the county. In County Council District 4, which includes the Laurel Park track, voters favor the zoning plan to allow slots at the mall by a small margin. But in the council district that includes the mall, District 1, more than half of the voters say they reject the zoning bill.

County Council members have long been divided over the slots plan, and approved the zoning bill in a split vote after nearly a year of rancorous debate. Horse racing interests immediately launched a petition drive to overturn the bill, leading to the referendum.

The ballot question campaign has become one of the most heated of the election season. The vote will determine if Cordish Cos. can build a planned 4,750-machine slots parlor adjacent to Arundel Mills, which could be the state's most lucrative casino in a gambling program that has lagged since voters approved it in a 2008 statewide vote.

Just one of five approved casinos — in Cecil County — has opened, a disappointment to those who anticipated a flow of revenue for state and local jurisdictions. In addition to Anne Arundel's, Baltimore's casino is also on hold.

With neighboring states that allow slots already responding to competition by approving table games, some politicians in Maryland are discussing expanded gambling options here.