By Hilary Russ

(Reuters) - Workers at four casinos in Atlantic City, New Jersey's gambling hub, turned out to vote on Thursday on whether to authorize a strike if they are not offered what they consider to be a fair contract by the start of the busy July 4 holiday weekend.

A strike vote could give Unite Here Local 54 bargaining committees more firepower in negotiations over new contracts for the 6,000 cocktail servers, cooks, housekeepers and other hospitality workers. Employees are now working under expired contracts.

"The vote today was that if we don't have a fair contract offer, we are walking on July 1," Local 54 President Bob McDevitt told reporters in a conference call.

Four of Atlantic City's casinos closed in 2014 and remain shuttered, in part because of gambling competition from neighboring states.

Workers who made contract concessions during those tough days say it is time for the casinos to give back now that there are signs of improvement at the eight that remain.

Unite Here said workers agreed to wage freezes during the recession, and those with 25 years on the job have had only 80 cents in total raises over the last 12 years.

"We've taken care of the companies over the years so we feel it's time that they give back to us now," said Chuck Baker, a relief cook for 26 years at the Trump Taj Mahal who joined the conference call.

Atlantic City casino revenues increased 2.7 percent to $802.6 million in the first quarter of 2016, according to state data.

The polls close at 8 p.m. Eastern time (0000 GMT Friday), and an affirmative vote would mean about 6,000 workers across five casinos would have authorization to strike.

Last summer, workers at the Trump Taj Mahal, founded by Donald Trump but now owned by billionaire investor Carl Icahn's Icahn Enterprises LP, agreed to allow a strike if needed. But they have yet to call a walkout, according to Local 54.

Thursday's strike vote pertains to the Tropicana casino and two properties, Caesars Atlantic City and Bally's Atlantic City, currently owned by bankrupt Caesars Entertainment Operating Company Inc.

Also included in the vote is another Caesars property, Harrah's Atlantic City, controlled by a separate unit not in bankruptcy..

Caesars' spokesman Stephen Cohen said the casinos are intent on hammering out a deal that benefits both workers and the city's comeback efforts.

"Our goal remains to negotiate a fair resolution to keep our employees at work and to continue supporting Atlantic City's revitalization, which has our full support," Cohen said in an email.

Last month, the U.S. Supreme Court rejected the union's appeal of a lower court ruling allowing the Taj Mahal to break its contract to secure a bankruptcy deal.

Separately, a U.S. judge on Wednesday temporarily halted lawsuits seeking $11.4 billion in damages from Caesars Entertainment Corp. in the bankruptcy of its operating unit.

(Additional reporting by Barbara Goldberg in New York; Editing by Diane Craft and Dan Grebler)