The Culinary Workers Union in Las Vegas has reached a tentative deal with casino giant Caesars Entertainment that could help avert a sweeping strike. The 5-year deal announced Wednesday by the union marks a major breakthrough after several months of unsuccessful negotiations. It comes just days before tens of thousands of hospitality workers could walk off the job and onto picket lines. Deals haven’t been reached with MGM Resorts International and Wynn Resorts. The tentative agreement with Caesars could provide the momentum needed for the union to win new contracts for all 35,000 union members. They have been working under expired contracts at properties owned or operated by the casino companies.