Spending in the fight over Maryland gambling expansion passed the $90 million mark as both sides made their final push before Election Day.

MGM Resorts International, which likely would operate a planned casino in Prince George's County if expansion passes, brought its contributions up to nearly $40.8 million. Caesars Entertainment, which is set to operate a new Baltimore casino, has added nearly $4.6 million, while the developer of National Harbor, the Peterson Cos., has contributed nearly $1.7 million to For Maryland Jobs and Schools, the committee in support of the expansion.

Caesars and Peterson also have spread about $2.8 million among three smaller committees in support of expansion.

Penn National Gaming brought its contributions to Get the Facts - Vote No on 7, the anti-gambling expansion committee, up to more than $42 million. Penn operates a casino in West Virginia that draws many Maryland residents, as well as a slots site in Perryville, Md., near the Delaware border.

If Question 7 passes, Maryland would allow table games, round-the-clock operation and a casino in Prince George's County.

(View sample ballots for Montgomery and Prince George's counties)

Both sides have made heavy use of television and radio commercials, along with rallies, social media posts, road signs and door-to-door canvassing, to get their message out.

"We're working every day with our broad base of supporters from elected officials like [Prince George's County Executive] Rushern Baker and business leaders to labor unions and community leaders," For Maryland Jobs and Schools spokeswoman Kristen Hawn said in an email.

Kevin McLaughlin, spokesman for Get the Facts, called the race a "dead heat."

"I think it's all going to come down to turnout," he said. "We will be doing everything under the sun to make sure our voters are getting out to the polls."

An Election Day loss would likely mean the end of casino plans in Prince George's, at least for the time being. MGM CEO James Murren told the Baltimore Business Journal Monday that the company would respect voters' wishes, saying, "We're going home" if the measure fails.