SHARE 2 4 COMMENTMORE

SEATTLE (KSDK) – The future of Boeing's new 777x jetliner is now in the hands of the workers who want to build it.

A critical union vote is underway that could either guarantee it is built in Washington state, or ensure that the Boeing company continues to look for another location. Boeing says the decision is up to the machinists.

Missouri and Illinois are two of 22 states offering up billions in free land, tax breaks and other assorted perks to land an estimated 8,500 high-paying jobs.

RELATED: Author: Boeing tax perks conspiracy on the public

One of the machinist's biggest sticking points with Boeing's current proposal is the transition from a pension plan to a 401k. A lot of workers say they're not willing to make that trade.

The polls close at 6 p.m. Seattle time at all five of the Union Hall locations. The result of the vote should be known by 9 p.m. Seattle time.