ATLANTIC CITY, N.J. — Federal lawmakers who represent New Jersey from both parties have asked the U.S. Justice Department to keep Internet gambling legal.

In a letter Thursday to Deputy Attorney General Rod Rosenstein, the lawmakers urged the department not to rescind its 2011 legal opinion that says Internet gambling is permissible under federal law.

Internet gambling is a thriving industry in New Jersey, helping Atlantic City’s seven casinos recover from a three-year period in which five of the city’s 12 casinos closed. The additional money brought in online often makes the difference between an up month and a down month for Atlantic City casinos.

Figures released Friday show Atlantic City’s casinos won $245 million online in 2017, an increase of nearly 25 percent from a year earlier.

Only four states — New Jersey, Nevada, Delaware and Pennsylvania — have legalized Internet gambling, and New Jersey’s regulatory standards are considered the strictest in the nation.

But the New Jersey lawmakers said their state has proven online gambling can be done safely and responsibly.