National Football League players were among the first to express their support. Then came Stacey Abrams, the Democratic star who helped turn Georgia blue in the 2020 election.

Actor Danny Glover traveled to Bessemer, Ala. For a press conference last week, where he spoke about the union-friendly leanings of Rev. Dr. Martin Luther King Jr. called to urge workers in the Amazon warehouse there to organize. Tina Fey weighed, as did Senator Bernie Sanders.

And on Sunday, President Biden made a resounding declaration of solidarity with the workers who are now voting on whether to form a union in Amazon’s Bessemer camp without naming the company. His video, posted on his official Twitter account, was one of the most haunting statements in recent history in support of union formation by an American president.

“Every worker should have a free and fair choice to join a union,” said Biden.

A union campaign that had purposely stayed under the radar for months has turned into a showdown with stars in recent days to influence workers at Amazon, one of the world’s dominant corporations whose power has grown exponentially during the pandemic. On one side is the retail, wholesale and department store union and its many work-friendly allies in politics, sports and Hollywood. On the flip side, it’s an e-commerce behemoth that has fought off previous union efforts in its U.S. facilities in its more than 25-year history.

This union vote in a referendum not only draws attention to the working conditions in the Bessemer camp, which employs 5,800 people, but also, in particular, to the plight of low-wage and color workers. Many of the workers at the Alabama camp are black, a fact that union organizers highlighted in their campaign to link the vote to the struggle for civil rights in the south.

The Retail Workers Union has a long history of organizing black workers in the poultry and food industries and helping them obtain basic benefits such as paid time off and safety protection, as well as a means of economic security. The union portrays its efforts in Bessemer as part of that legacy.

“This is an organizing campaign on the right to work in the south during the pandemic at one of the largest companies in the world,” said Benjamin Sachs, professor of work and industry at Harvard Law School. “The importance of a union victory there really couldn’t be emphasized enough.”

Warehouse workers began voting by post on February 8, and ballots are due by the end of that month. A union can be formed if a majority of the votes cast is in favor of such a move.

Amazon’s counter-campaign, both inside the warehouse and nationally, has focused on pure economics: the starting wage is $ 15 an hour plus benefits. That’s far more than the competition in Alabama, where the minimum wage is $ 7.25 an hour.

“It is important that employees understand the facts of union membership,” said Heather Knox, an Amazon spokeswoman, in a statement. “We will provide information about this and the electoral process so that you can make an informed decision. If the union vote is successful, it will affect all local employees, and it is important that employees understand what this means for them and their daily lives at Amazon. “The company, which went through a major hiring frenzy last year when domestic customers had sales of $ 386 billion, posted profits of more than $ 22 billion.

In Alabama, some workers are getting tired of the process. One employee recently posted on Facebook: “This union stuff is getting on my nerves. Let it be March 30th !!! “

The situation is getting worse and union leaders accuse Amazon of a number of “anti-union” tactics.

The company has posted signs throughout the warehouse, next to hand disinfection stations and even in toilet cubicles. It sends texts and emails regularly and draws attention to the problems with the unions. The internal company app publishes photos of employees in Bessemer showing how much they love Amazon.

During certain training sessions, company representatives have pointed out the cost of union dues. If some workers asked specific questions in the meetings, then the representatives from Amazon followed them in their workplaces and again emphasized the disadvantages of unions, say employees and organizers. The meetings were called off when the voting began, but the signs are still there, said Jennifer Bates, a union-friendly worker at the warehouse.

In this charged atmosphere, even routine matters have become suspicious. The union has raised questions about changing the timing of a traffic light near the warehouse where work organizers try to speak to workers if they are stopped in their vehicles as they exit the facility.

Amazon asked district officials to change the timing of the light in mid-December, although there is no evidence in the district’s records that the change was made to thwart the union. “Traffic for Amazon is secured by changing shifts,” said the public records as the reason the district changed the light.

Amazon regularly navigates to traffic issues at its facilities, and wasting unpaid time in congested parking lots is a common complaint from Amazon employees on Facebook groups.

However, retail workers union president Stuart Appelbaum questioned the timing of the request in Bessemer, as it did at the height of the organization. “When the light was red, we could answer questions and have a quick chat with the workers,” he said.

Last week the union questioned an offer by the company to Alabama warehouse workers to pay them at least $ 1,000 if they quit by the end of March.

“They are trying to remove the most likely union supporters from their workforce by bribing them to leave and giving up their vote,” said Appelbaum.

But “The Offer,” as it is known among employees, was the same thing Amazon made to workers in all of its warehouses across the country. It’s an annual program that allows the company to reduce its headcount without layoffs after the busy season. It’s been around since at least 2014 when Jeff Bezos wrote about it in a letter to shareholders.

“Once a year we offer our employees to pay for the termination,” said Bezos at the time.

Mr. Appelbaum was not influenced. He said he believed Amazon decided to make the offer in all camps to rule out possible yes votes in Bessemer.

Mr Biden stopped pushing Amazon workers to unionize, but his testimony immediately increased the streak of an already momentous campaign.

“Let me be really clear,” said Mr Biden. “It’s not up to me to decide whether anyone should join a union. But let me be even more clear: It is not up to an employer to decide either. The decision to join a union rests with the workers. Point.”

He added, “Workers in Alabama and across America are voting on whether to unionize in their workplace. This is critical – an extremely important decision. “And it is one, he said, that should be done without intimidation or threats.

Despite the union’s suspicions, she has not filed any formal complaints with the National Labor Relations Board, Appelbaum said. Typically, unions can object to a company’s tactics before an election and the labor authority can intervene.

Should a complaint be filed, the labor authority may find that the election is invalid due to Amazon’s actions. After months of working to build support inside and outside the Amazon camp, the union’s last thing they want is for the labor authority to step in and decide that the elections must be held again.

Harvard Law School’s Mr Sachs said that, despite Mr Biden’s admonitions to meddle in elections, the current labor law allows Amazon to hold certain mandatory meetings with workers to discuss why they should not union and this enables the company to post anti-union messages in the workplace.

By aggressively targeting the union, Amazon risks angering the Washington Democrats, many of whom are already calling for greater antitrust control over large tech companies. Amazon launched a public campaign in support of legislation to raise the federal minimum wage to $ 15 an hour and bought prominent ads in the New York Times, Washington Post, and other publications.

In his video on Sunday, President Biden specifically mentioned how unions can help “black and brown workers” and vulnerable workers struggling during the economic crisis sparked by the pandemic.

Ms. Bates, 48, one of the leaders of the union action, started working in the Bessemer camp in May.

She said she was offended by some anti-union efforts by Amazon, particularly what the company told employees that they had to pay nearly $ 500 in union dues every year. Because Alabama is a right to work, there is no such requirement that an employee pay dues in a unionized workplace.

“It annoys me a little because I feel like they know the truth and they are not telling the truth and they take advantage of them because they know that employees come from a community that is considered black and low-income,” said Mrs. Bates, who is black. “It felt really horrible that you were standing there deliberately misleading people. Give them the facts and let them decide. “