CHICAGO — Hotel workers in Chicago entered their fourth day on strike Monday, picketing outside six downtown hotels and pressing for higher wages and better health care benefits. Workers walked off the job Friday morning, choosing the Chicago Marathon weekend to draw attention to the contract dispute, according to the union. Their contracts with Hilton, Marriott and Hyatt had expired. Cooks, servers, housekeepers and front-desk assistants were among those on the picket lines. At the Palmer House, demonstrators gathered outside both the Monroe Street and Wabash Avenue entrances. Hotel employee Zeruiah Eason said the picket lines are intended to affect hotel operations and bring pressure to bear on management. The crowds and noise have also affected businesses beyond the hotels. Sugar Bliss, an independent bakery located inside the Palmer House, said its walk-in business fell sharply over the marathon weekend. Owner Teresa Ging said the bakery lost 70% of its business on Friday and Saturday, typically important days for the business. Catering and shipping have helped it continue operating, she said. A union official urged people affected by the demonstrations to contact the hotels and ask them to reach agreements with workers. No details of proposed wage increases, benefit changes or a negotiation timeline were provided.