MGM is angling to build a casino at National Harbor in Prince George’s County. (Linda Davidson/The Washington Post)

A late infusion of cash from proponents of expanded gambling in Maryland has pushed the total tab for the campaign over Question 7 to more than $90 million.

MGM Resorts, the company angling to build a Las Vegas-style casino at National Harbor, in recent days poured another $11 million into the primary ballot-issue committee fighting for passage of Question 7. That brings MGM’s total outlay to $40.8 million, according to a disclosure form made public Monday, the day before the election.

The Peterson Cos., the developer of National Harbor, meanwhile, put another $2 million into a second pro-expansion committee led by former Prince George’s County Executive Wayne K. Curry.

With its latest contribution, Peterson has now spread nearly $4.3 million among three different committees registered to advocate for Question 7.

The ballot measure would allow a new casino in Prince George’s, as well as table games, such as blackjack and roulette, at Maryland’s five previously authorized slots sites.

The only large funder of the opposition has been Penn National Gaming, which has now contributed $42 million to a ballot-issue committee seeking to defeat Question 7.

Penn’s properties include a casino in Charles Town, W.Va., that analysts say would take a financial hit if another large-scale gambling venue is built in Maryland.

With MGM’s latest contribution, it has now allocated nearly as much as Penn National for the battle.

A group led by Caesars Entertainment has also kicked in nearly $4.9 million to committees registered to advocate for Question 7. Caesars plans to open a casino in Baltimore in 2014 that would benefit from table games.

Companies with a stake in the outcome of Question 7 have also contributed money to a committee advocating passage of all seven ballot measures on Tuesday, as well as to one led by Republicans that is urging passage of expanded gambling but defeat of same-sex marriage and the so-called Dream Act.