On a recent night, sandwiched between television coverage of Olympic dressage and synchronized diving, a commercial touted the benefits of a new casino at National Harbor in Prince George's County.

"Good-paying jobs. Better schools," said a man's voice. "But it won't happen if the special interests get in the way."

Within minutes, a woman in another ad warned that the state legislature is rushing a deal to build a casino at National Harbor. The culprit? "Casino special interests," she said.

The commercial matchup, on all major networks in Baltimore, is part of an onslaught of ads focused on the issue of whether to expand casino gambling in Maryland.

Supporters and opponents have spent more than $1.1 million for television and radio ads over the past eight weeks, and more are expected in the days leading up to Thursday's special session of the General Assembly. The pricey prime-time ads are highly unusual for moderate Maryland, which, outside of gambling, rarely sees expensive issue campaigns.