Las Vegas hotel worker unions are pushing for Barbra Streisand to cancel her $ 20 million New Year’s gig at the new MGM Grand Hotel to protest the resort’s refusal to use union workers.

High-ranking union sources said Friday the coalition would go all-out to convince Streisand to cancel the shows, her first paid concert appearances in 27 years.

“If this were happening anywhere but Vegas,” said one union source, “Streisand wouldn’t get anywhere near it … We’re going to tell her that she shouldn’t have anything to do with it.”

The unions are angry with MGM Grand CEO-president Bob Maxey, who they claim has a long record of abusing the rights of workers, and specifically women. The last hotel he ran, the Rio Suites Hotel, is currently under investigation for at least seven sexual harassment claims filed with the Equal Opportunity Commission, union sources said.

Streisand recently inked the deal to sing at the Grand for an unheard-of $ 10 million a night for New Year’s Eve and Jan. 1. The 5,000-room resort, which has a 33-acre theme park and cost $ 1 billion, is skedded to open Dec. 18.

Union sources said they were surprised MGM Grand opted to go non-union, when four of Vegas’ newest hotels, including the Luxor and Treasure Island, employ union workers. They said 85% of Las Vegas hotel workers belong to unions.

The coalition includes just about every major hotel worker union in Vegas — the Culinary Workers Local 226, the Teamsters, stagehands, musicians, engineers, service employees and food workers. They say more than 5,000 jobs will be affected by the MGM Grand’s decision.

Streisand could not be reached for comment. A spokesman for Maxey and the MGM Grand said he had not heard of the protest and declined to comment.

The unions are banking on Streisand’s sentiment for women’s causes. “She has always been open to the women movements around the country. Hopefully, she’ll listen to us,” said Wanda Henry, a former cocktail waitress who is leading the protest for Local 226.

The unions concede that the MGM Grand has offered wages and benefits comparable to the union’s but complain that the hotel provided no job security.

But the big selling point for Streisand, they hope, will be the stream of alleged sexual harassment at the Rio Suites.

They claim that in 1991 when Maxey ran the Rio Suites — one of the few non-union hotels in Vegas — he forced cocktail waitresses to wear outfits so skimpy they resembled strippers. The unions also allege he fired pregnant women who could no longer fit into the uniforms.

At a hearing Friday in Las Vegas, former employees told U.S. Dept. of Labor rep Karen Nussbaum of horror stories at the hotel.

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