Table games, including craps, will become legal in Maryland if Question 7 passes in November. (AP Photo/Wayne Parry)

Penn National Gaming, which opposes Question 7 on next month’s ballot, reported spending another $3.5 million, bringing its total for the campaign to $21.6 million.

MGM Resorts, a company angling to build a new casino at National Harbor, reported additional expenditure of nearly $3 million, increasing its total outlay to $14.4 million.

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

Money is flowing from the companies to ballot-issue committees set up to fight for and against the referendum, largely through TV advertising.

Besides MGM, other proponents of the plan that have given money include the Peterson Cos., the developer of National Harbor, which has contributed $1.3 million, and a group led by Caesars Entertainment, which has given $3.4 million.

Caesars is planning to open a Harrah’s-brand casino in Baltimore in 2014 and wants to include table games.

So far, Penn is the only company funding the opponents.

Penn owns Rosecroft Raceway, a Prince George’s facility that would be eligible to bid for a casino license if the expansion plan passes. But Penn officials argue that the deck is stacked against them, because Prince George’s County Executive Rushern L. Baker III (D) and others have championed National Harbor as a better casino site.

Penn also owns a casino in Charles Town, W.Va., that analysts say would take a significant hit if another large-scale venue opens in Maryland. Proponents of the measure have accused Penn of acting to protect its interests in Charles Town.

The company also owns a smaller casino in northeastern Maryland which stands to benefit from table games if the ballot measure passes.