Amazon.com Inc.¡¯s fierce resistance to unionization, skepticism among workers that organizing could get them a better deal and decisions on election parameters all contributed to the apparently lopsided defeat of a labor drive at the company¡¯s warehouse in Bessemer, Alabama, people close to the events said.

A vote by workers on whether to unionize failed on Friday by a more than 2-to-1 margin in a major win for the world¡¯s largest online retailer. The union plans to challenge the results based on Amazon¡¯s conduct during the election.

Union leaders had hoped the campaign just outside Birmingham would create Amazon¡¯s first organized workplace in the U.S. and spark a new era of worker activism. Instead, it has illustrated the continued challenges facing the labor movement in America.