TRENTON -- In 2008, Gov. Jon Corzine signed a law designed to prevent Atlantic City's casinos from closing if there were ever another state government shutdown sparked by a state budget disagreement.

But now, with the state under shutdown again, some leaders are worried a little-known provision in the 2008 law allows casinos to shutter if the budget impasse lasts beyond seven days.

That means casinos could shutter as early as Saturday. The state stands to lose millions in casino tax revenue -- and the struggling casino industry would be hit hard -- if that happens.

With the shutdown set to enter its third day Monday, such a threat could invigorate talks to end the budget stalemate sooner than later.

Gov. Chris Christie ordered nonessential parts of the state government -- such as state parks and beaches and Motor Vehicle Commissions -- to close Friday amid a disagreement that caused state lawmakers to fail to pass a budget by the July 1 deadline.

But Christie said Sunday that his "initial reading" of the 2008 law is that "it's a seven-day extension beyond" the first day of the shutdown.

Christie said he is having state Attorney General Christopher Porrino look into the matter.

"Whether there are some exceptions that can be made or something else through an executive order or some other action by the governor, the attorney general was looking into that," the governor said at a news conference. "Once I have that answer I'll get back to you guys and let you know."

During the 2006 government shutdown -- the first in state history -- Atlantic City's 12 casinos closed for three days, costing the state $4 million in casino tax revenue because gambling regulators and inspectors were not allowed to work.

The city's casino revenues dropped 4.8 percent that July compared to the year before. In addition, about half of the casinos' 46,000 workers were idled and lost about $9 million to $10 million in wages and tips, officials said at the time.

In 2008, two years after the shutdown, Corzine signed a law saying casinos and tracks could not shutter during budget fights.

But state Sen. Jim Whelan (D-Atlantic), the sponsor of the legislation, said the seven-day provision is "what we needed to do to get the bill through."

"We wanted it to be just: Don't close the casinos," said Whelan, a former Atlantic City mayor. "It doesn't make any sense. You're going to close a source of income that pays for itself?"

Atlantic City now has seven casinos in the wake of an industry downturn, so losses would not be as large if there were a similar scenario now. Still, any losses could be damaging not only to the state but to the city, which has has seen signs of improvement in recent months after being on the brink of bankruptcy last year.

At the heart of the new budget impasse is a battle over a bill that would reform Horizon Blue Cross Blue Shield of New Jersey, the state's largest health insurance provider. Christie wants the bill in exchange for signing Democrats' state budget.

State Senate President Stephen Sweeney (D-Gloucester) has agreed to the deal, fearing that Christie would veto Democratic priorities out of the budget. But state Assembly Speaker Vincent Prieto (D-Hudson) has refused to post the Horizon measure, holding up the budget.

Sweeney wondered Sunday whether opponents of the Horizon bill are delaying negotiations to force the casinos to close. Sweeney is a south Jersey lawmaker, and many of his constituents work at the casinos in nearby Atlantic City.

"They really want to shut the casino down, Horizon, by not wanting to talk to us?" Sweeney asked.

But Tom Hester, a spokesman for Prieto, noted that the speaker and Horizon CEO Bob Morino have agreed to meet with Sweeney at 1 p.m. in Trenton to discuss a compromise on the Horizon bill to end the shutdown.

Meanwhile, Assemblyman Vincent Mazzeo (D-Atlantic) has introduced a bill that would remove the seven-day provision. But it's unclear if either house of the state Legislature would vote on it during the shutdown.

Whelan had a simple response for what would happen if casinos do close.

"It's going to hurt the state," he said.

NJ Advance Media staff writers Claude Brodesser-Akner, Susan K. Livio, and Samantha Marcus contributed to this report.

Brent Johnson may be reached at bjohnson@njadvancemedia.com. Follow him on Twitter @johnsb01. Find NJ.com Politics on Facebook.