Culinary Union leaders wrap up a vote on whether to authorize a strike Tuesday, May 22, 2018, in Las Vegas. A potential strike would affect 34 casino-hotels. A majority yes vote would not immediately affect the casinos, but it would give union negotiators a huge bargaining chip by allowing them to call for a strike at any time starting June 1. (AP Photo/Isaac Brekken)

LAS VEGAS — Unionized Las Vegas casino workers descended on a university arena in red T-shirts and work uniforms as they voted Tuesday on whether to call for a citywide strike that could have huge financial implications for the tourist-dependent destination.

Ballots were cast in two sessions expected to draw as many as 25,000 members of the Culinary Union and show the collective power of the largest labor organization in Nevada.

A majority yes vote would not immediately affect the casinos but would give union negotiators a huge bargaining chip by allowing them to call on a strike at any time starting June 1.

“I’m here to show the younger generations that this is the way we fight to maintain our jobs, job security, health benefits and to gain a pay raise,” said Lewis Thomas, a utility porter at the Tropicana casino-hotel. “This will be a wake-up call to let (the companies) know we are together, we are united, we are not separated.”

The voting came as the contracts of 50,000 unionized workers were set to expire at midnight May 31 and negotiations with individual casino-operating companies for new five-year contracts have not led to agreements.

The union last voted for a strike in 2002 but reached a deal before employees walked off the job. The last strike spanned 67 days more than three decades ago and cost the city millions of dollars.

This time, the move could hobble 34 properties as they lose bartenders, housekeepers, cocktail and food servers, porters, bellmen, cooks and other kitchen workers. It also could cause problems for fans heading to the city to watch the Vegas Golden Knights hockey team play in the Stanley Cup Final in early June.

Union members — some attending with their young children — high-fived, took selfies and video, and carried signs urging people to vote Tuesday at the Thomas and Mack Center at the University of Nevada, Las Vegas.

Outside the arena, pro-union chants in English and Spanish welcomed workers. Some chanted, “Hey, Caesars, look around, Vegas is a union town” and “No contract, no peace.” Banners read, “Show up or give up, security strike vote.”

Inside, workers dropped paper ballots into numbered boxes. Some workers stopped by in their uniforms on their way to or from work, while others wore shirts emblazoned with “Vegas Strong” and the union logo.

Union officials have said they want to increase wages, protect job security against the increasing use of technology at hotel-casinos, and strengthen language against sexual harassment.

“We’ve been in negotiations with the companies, and they are not giving the workers what they deserve according to the economy right now,” Geoconda Argüello-Kline, union secretary-treasurer, said after the first voting session. “They are very successful. They have a lot of money.”

MGM Resorts International and Caesars Entertainment operate more than half of the properties that would be affected by a strike. MGM said it will keep meeting with the union.

“As we continue to bargain in good faith, we are confident that we’ll resolve contract issues and negotiate a contract that works for everyone,” the company said in a statement.

Caesars did not immediately respond to a request for comment.

When casino workers across Las Vegas went on a strike in 1984, union members lost an estimated $75 million in wages and benefits and the city lost a similar amount in tourism revenue. Millions more were lost in gambling income.