NEW YORK (REUTERS) - Amazon warehouse workers in Alabama voted against forming a union by a more than 2-to-1 margin in a major win for the retailer, but the union hoping to reignite the US labour movement said on Friday (April 9) it would challenge the results, citing election interference.

The company's fierce resistance to unionisation, scepticism among workers that organising could get them a better deal and decisions on election parameters all contributed to the apparently lopsided defeat, which marks an important loss for US organised labour.

National Labour Relations Board representatives counted 1,798 voting against forming a union, with 738 ballots in favour. A simple majority was needed for victory.

Both sides have the right to challenge the eligibility of individual ballots and the campaign process, but a ballot count official on a Zoom call of the proceeding announced that there were not enough challenged votes to affect the results.

Amazon shares rose 1.7 per cent on Friday, adding to earlier gains.

Union leaders had hoped the election outside Birmingham would spark a new era of worker activism.

Appealing to concerns that Amazon was monitoring their every move and associating themselves with the Black Lives Matter movement, organisers told the largely Black workforce that a union could get more from the company controlled by the world's richest man.

The defeat joins high-profile failures to start unions at auto and plane factories in the US South, and illustrates the challenges of organising at a major company. Amazon required workers to attend meetings, for instance.

Still, some employees described relatively good conditions and pay. Amazon offers at least US$15.30 an hour, more than twice the federal minimum wage, which applies in Alabama.

"Amazon is not perfect, there are flaws, but we are committed to correcting those flaws and management has been, thus far, on board with us," William Stokes, an Amazon worker at the Bessemer warehouse, said at a panel organised by the company.

He voted "no" to the union.

The vote was watched across the United States, with President Joe Biden speaking in support of workers' right to form unions during the process.

The US South has been particularly anti-union. Nearly all the states in the area, including Alabama, passed so-called right-to-work laws that curtail unions' abilities to mandate dues and other measures.

What's next?

The Retail, Wholesale and Department Store Union (RWDSU), which is trying to organise the Amazon employees, said it is filing objections, charging that Amazon interfered with the right of employees to vote.

"People should not presume that the results of this vote are in any way a validation of Amazon's working conditions and the way it treats its employees, quite the contrary. The results demonstrate the powerful impact of employee intimidation and interference," Stuart Appelbaum, RWDSU president, told a news conference after counting ended.

"We contend that they broke the law repeatedly in their no-holds-barred effort to stop workers from forming a union." The dispute likely will play out before the National Labour Relations Board (NLRB) and then in federal appeals court.

Union membership has been declining steadily, falling to 11 per cent of the eligible workforce in 2020 from 20 per cent in 1983, according to the US Bureau of Labour Statistics.

Amazon, the second-largest private employer in America, for decades has discouraged attempts among its more than 800,000 US employees to organise, showing managers how to identify union activity, raising wages and warning that union dues would cut into pay, according to a prior training video, public statements and the company's union election website.

The union's objection will focus in part on what it described as Amazon coordinating with the US Postal Service to install a mail box on warehouse property and then pressuring employees to use it to vote. The union in a statement called this "unlawful ballot harvesting" and said it "allowed Amazon to determine who supported the Union" by seeing who declined the drop box's use.

An Amazon spokesman said the union had fought the company's proposals for different options to make voting easy and had pushed for a mail-only election.

"This mailbox - which only the USPS had access to - was a simple, secure, and completely optional way to make it easy for employees to vote, no more and no less," the spokesman said.

Out of 5,867 workers eligible to cast ballots, 3,041 voted.

NLRB officials said 505 ballots were contested and 76 were voided.

Richard Trumka, AFL-CIO president, who spoke at the union's press conference, said, "This is not the outcome any of us hoped for... but make no mistake, you won the moment that you decided to take on Amazon."