The animus between Comptroller Peter Franchot and Gov. Martin O'Malley is taking center stage in the Maryland slots contest, providing a lively sideshow to a years-old debate to be decided by voters next month.

Campaigning against legalization of slots yesterday in Northwest Baltimore, Franchot called on the pro-gambling governor to "cease and desist" what the tax collector described as "Swift boat-style" and " Karl Rove-style" attacks on him, according to prepared remarks.

Franchot was responding to a letter by the pro-slots ballot committee sent this week to Maryland elected officials that said Franchot "has spent the past year trying to run away from his 'pro' record on slots." Franchot co-sponsored slots legislation in 1998 and 2001, though he has been an ardent slots opponent in recent years.

O'Malley, through a spokeswoman, declined to respond to Franchot's statement.

Steve Kearney, a spokesman for the pro-slots campaign, For Maryland For Our Future, said the group is not personally attacking Franchot but is merely putting the comptroller's anti-slots zeal in its proper context. "There are honorable people on both sides of this debate," Kearney said, "but facts are facts, and correcting misinformation is not an attack."

Sen. James Brochin, a pro-slots Democrat from Baltimore County, said the increasingly combative tone of the campaign is no surprise.

"There's a lot at stake here, and I think both sides will pull out every single stop they think will influence voters," Brochin said. The referendum "will change the fabric and culture of Maryland for years to come, and nobody wants to say they didn't do everything they could to get slots passed or to get it defeated."

In November, voters will decide whether to amend the Maryland Constitution to allow five casinos across the state containing a maximum of 15,000 slot machines. Analysts estimate that more than $600 million annually could flow to public education and as much as $100 million a year to subsidies for the horse-racing industry.

Since his election two years ago, Franchot has repeatedly opposed O'Malley on spending and other statewide issues. Some in Annapolis speculate that Franchot is considering challenging O'Malley for governor, but Franchot denies interest.

Even as he decried criticism leveled against him, Franchot attacked O'Malley yesterday as "standing with the special interests" who would benefit from expanded gambling. The comptroller acknowledged that he once "believed the fairy tale that slots could solve our financial problems," but that, like the governor, his position on the issue has evolved.

As Baltimore mayor, O'Malley supported limited use of slots at racetracks to prop up the struggling horse racing industry but said it was a "pretty morally bankrupt way to fund education." But the governor guided the gambling referendum to passage during a special legislative session on budget-balancing last year.