"Make sure you take care of us!" a worker shouts to two union organizers in orange vests standing at the entrance of Amazon's warehouse in Bessemer, Alabama -- ground zero of a battle over unionizing the American retail giant.
The sun is not yet up, but the two organizers Steve and Syrena gamely wave their posters to catch the attention of night-shift workers pouring out of the huge facility and of day-side employees taking over on a foggy Saturday morning.
In the glare of car headlights, one can read the words on their posters -- "Thanks for your courage!" -- along with the initials RWDSU, for the Retail, Wholesale and Department Store Union, which will represent the warehouse's 5,800 employees if they support it in a vote ending Monday.
That would be a first in the United States for Amazon, which employs 800,000 people in the country, most of them in sorting, packaging and shipping centers like this one.
It would also be a major coup for a union movement in historic decline -- now representing only 11 percent of nonfarm American workers, down from 30 percent in 1964.
Coming at a time when the White House occupant, Joe Biden, has promised to be the country's "most pro-union president," it could open the floodgates to unionization efforts at other Amazon sites and other firms.
- A labor crossroads? -
For five months, union organizers in Bessemer have been posted at the intersection between a busy interstate highway and several hulking industrial buildings.
Behind them, banners calling on workers to vote hang from the immense white-and-gray warehouse, next to the illuminated, curved arrow resembling a smile -- Amazon's ubiquitous logo.
Steve has come almost every day -- three hours at dawn and three in the evening -- first to gather signatures demanding a vote on unionization, then to persuade Amazon workers to vote yes, and now to thank them for mobilizing.
"He's too modest to say it, but sometimes he would be signing 50 people in a day," said Syrena, who, like Steve, declined to give her last name.
The vote ending Monday is overseen by the National Labor Relations Board.
- 'Informational' meetings -
More than 3,000 employees have signaled their tentative support, but victory is far from certain.
Amazon, while not officially declaring opposition to unions, has waged a determined campaign, holding weekly "informational" meetings, sending text messages and putting up posters in restrooms in an all-out effort to defeat the union initiative.
Union organizers say they even suspect that the company may have pressured local officials to speed up the red light at the intersection where they stand to reduce the time that organizers have to speak to drivers.
"For 24 hours a day seven days a week we did not leave the gates, and so we became very familiar with the traffic patterns and the red lights," said Joshua Brewer, president of the union's local branch, "and suddenly they changed."
Lafonda Townsend said she cast a "yes" vote in hopes the union can negotiate better working conditions, including improved protection against Covid-19.
Amazon workers around the country have complained they are pressed to work at an unrelenting pace, with little time even for bathroom breaks.
Townsend said the company was summoning workers to required meetings as often as three times a week.
"They had these charts up where there's things like: you don't need a third-party person to speak for you" and warning that union dues could reach $500 a year, Townsend told AFP.
- Text messages -
"You will get a lot of text messages from Amazon and they will tell you to vote no," said Frances Wallace, a 20-year-old Amazon employee who joined a pro-union demonstration Saturday.
She showed one of the messages: "J.C. 43 has been working at Amazon since April and loves it. The job provides affordable medical, dental and vision benefits for his family, which saves him $800 a month and helped pay for his two sons' braces... He voted no."
Suspicion runs deep in Bessemer after months of rumors and tension.
Amazon has defeated every previous union effort in the US, though most of its operations in Europe are unionized.
Joshua Brewer is hopeful, but he has seen the toll taken on workers by the company's intense campaign.
"I would say that you know corporations often fight union drives, but this level of sophistication and really fear, that is something we've never seen before," he said.
Asked to comment in February, Amazon pointed to its creation of more than 5,000 jobs; to its relatively high pay levels ($15.30 an hour, more than twice the legal minimum wage in Alabama); and to benefits like health, vision and dental insurance.
"More than 90 percent of associates at our Bessemer site say they would recommend Amazon as a good place to work," said an Amazon spokeswoman, Heather Knox.