Amazon could not be reached for immediate comment.
The vote itself has garnered national attention, with professional athletes, Hollywood stars and even President Joe Biden weighing in on the side of the union.
If the union wins, it would be the first in Amazon's 26-year history. But the vote also has wide-reaching implications beyond Amazon, which is now the second-largest private employer in the U.S. after retailer Walmart.
Whatever the outcome, labor organizers hope Bessemer will inspire thousands of workers nationwide — and not just at Amazon — to consider unionizing. For Amazon, which has more than 950,000 workers in the U.S. and has fought hard against organizing attempts, a union loss could chill similar efforts around the company.
The labor board has already reviewed each vote, reading names and signatures on the envelopes with representatives from Amazon and the retail union, both of which had a chance to contest those votes. Contested votes were put to the side and not opened.
Now the board is opening the uncontested votes from their envelopes and counting “yes" or “no" votes.
Even if there's a clear winner, the battle may be far from over. If workers vote against forming a union, the retail union could file objections accusing Amazon of tainting the election in some way, which could lead to to a redo of the election if the labor board agrees. Amazon could file its own objections if the workers vote to form a union.
Follow Joseph Pisani on Twitter: @ josephpisani