A labor official is confirming a new union election for Amazon workers in Bessemer, Alabama based on objections to the first vote.

The rare move was first announced on Monday by the Retail, Wholesale and Department Store Union, which spearheaded the union organizing movement. A National Labor Relations Board spokeswoman confirmed the decision.

The move is a major blow to Amazon, which had spent about a year aggressively campaigning for warehouse workers in Bessemer to reject the union, which they ultimately did by a wide margin.

But even with a second election, labor experts say a union victory is a long shot. Amazon will likely appeal and try to delay another vote. And even when an election is held, workers may chose to vote against joining a union again. Last time around, 1,798 workers rejected the union and 738 voted in favor of it.