Money continues to pour into Maryland’s gambling campaign.

Maryland’s ballot measure would allow Las Vegas-style table games, including craps, as well as a new casino in Prince George’s County. (AP Photo/Wayne Parry)

Penn had previously given about $5.5 million to the campaign, which is playing out in ubiquitous television ads in both the Washington and Baltimore markets.

On the other side, MGM Resorts, the company angling to operate a new casino at National Harbor, has contributed about $5.4 million, while the Peterson Cos., the developer of National Harbor, has chipped in $400,000.

A group led by Caesars Entertainment that has a license to operate a Baltimore casino has also pledged to support the pro-expansion cause.

Question 7 on Maryland’s ballot would allow a new casino in Prince George’s County, as well as Las Vegas-style table games, such as black jack and roulette, at the state’s five previously authorized slots venues.

Penn, which already owns one casino in Maryland, would be eligible to bid for the Prince George’s license and has proposed putting a casino at Rosecroft Raceway.

But the company argues the deck is stacked against Rosecroft because Prince George’s County Executive Rushern L. Baker III (D) and others have championed National Harbor as a site.

Penn also owns a casino in Charles Town, W.Va., that stands to lose more of its customers from Maryland if gambling expands in the Free State.

While Caesars would not benefit from another competitor, the company has said it supports the expanded gambling plan because it would allow its Baltimore facility to have table games and a more favorable tax rate.