Union leaders expect a close vote when 3,000 Boeing hourly workers weigh a sweetened contract offer that could end an almost six-week strike, the union's chief said Tuesday.The vote will take place throughout Wednesday,

Their work stoppage has halted production of the plane maker's best-selling 737 MAX and its 767 and 777 widebodies.

The deal reached by the machinists union, which represents more than 33,000 workers, would cumulatively raise wages by nearly 40 percent over four years, according to details shared by the union.