NEW YORK – Rush Limbaugh’s opponents are starting a radio campaign against him, seizing upon the radio star’s attack on a Georgetown law student as a “slut” to make a long-term effort aimed at weakening his business.

The liberal Media Matters for America is using a past campaign against conservative commentator Glenn Beck as a template. In Limbaugh, however, they’re going after bigger game. He’s already fighting back, and the group’s stance has provoked concerns that an effort to silence someone for objectionable talk is in itself objectionable.

Media Matters is spending at least $100,000 for two ads that will run in eight cities. The ads use Limbaugh’s own words about student Sandra Fluke, who told congressional Democrats that contraception should be paid for in health plans.

Limbaugh, on his radio programs, suggested Fluke wanted to be paid to have sex, which made her a “slut” and a “prostitute.” In return for the money, he said Fluke should post videos of herself having sex. Under sharp criticism, he later apologized.

In one of the anti-Limbaugh ads, listeners are urged to call the local station that carries Limbaugh to say “we don’t talk to women like that” in our city.

Ad time was purchased in Boston, Chicago, Detroit, Seattle, Milwaukee, St. Louis, Macon, Ga., and Cedar Rapids, Iowa. The cities were selected to support active local campaigns against Limbaugh or because of perceptions that he may be vulnerable in that market, said Angelo Carusone of Media Matters.

A spokeswoman for Premiere Radio Networks, which syndicates Limbaugh’s show to nearly 600 radio stations nationally, said Media Matters has gone beyond criticism of Limbaugh’s words to an attempt to silence him and intimidate advertisers.

“This is not about women,” said Rachel Nelson, Premiere spokeswoman. “It’s not about ethics and it’s not about the nature of our public discourse. It’s a direct attack on America’s guaranteed First Amendment right to free speech. It’s essentially a call for censorship masquerading as high-minded indignation.”

Limbaugh, on his radio show Wednesday, said he’s being targeted in an attack that was long-planned — not mentioning it was his words that lit the fuse.

Cashing in at Margaritaville casino

LAS VEGAS – Nevada gambling regulators have approved a license that will let singer-songwriter Jimmy Buffett share in the gambling revenues from his Margaritaville casino in Las Vegas.

The Las Vegas Review-Journal reported that the Nevada Gaming Commission unanimously approved a gambling license Thursday for Palm Beach, Fla.-based Margaritaville Holdings and its famous chairman, Buffett.

The casino, located inside the Flamingo on the Las Vegas Strip, opened in October. Buffett has had a presence in Sin City since 2003 through his Margaritaville restaurant.