By Sebastian Herrera

Federal labor authorities rejected Amazon.com Inc.'s request to delay a union election at one of its warehouses in Alabama, clearing the way for thousands of workers to begin casting their votes this month.

The National Labor Relations Board Friday denied Amazon's request, saying the company didn't raise any substantial issues warranting review of the election. The online shopping giant in late January asked the board to postpone the union vote scheduled to begin Monday at its facility in Bessemer, Ala. Amazon also requested that authorities reconsider a decision to allow mail-in voting due to the pandemic. The workers have until late March to return their ballots in an election that could reshape Amazon's relationship with its hourly employees.

Amazon declined to comment.

"It's long past time that Amazon start respecting its own employees," said Stuart Appelbaum, president of the Retail, Wholesale and Department Store Union, or RWDSU, which would represent the workers if they vote to unionize. Amazon must allow its workers "to cast their votes without intimidation and interference."

The union, which has become a frequent Amazon antagonist in recent years, has sought to garner support by rallying employees through family members and union members who work in other industries. Workers who want unionization said it would allow them to collectively bargain over safety standards, training, breaks, pay and other benefits. Amazon employees have never formed or been part of a union in the U.S., and labor experts say unionizing in Bessemer could lead to similar efforts at other Amazon facilities.

Organizers launched their campaign in the fall and collected thousands of worker signatures in support of the union. They have set up a presence outside near the 855,000-square-foot warehouse almost daily, talking to workers at a stop light and handing them fliers.

Amazon, which has long opposed unions, launched a website to encourage employees to vote against unionizing and has been holding frequent meetings inside the facility to counter the union's effort, according to employees. It has also posted signs around the warehouse. Amazon has said that it provides workers with ample benefits and doesn't believe the union represents the majority of employees' views.

Labor experts say that while the current effort has had more success than other attempts to organize at Amazon, it will be difficult for organizers to achieve their goals. Amazon has easier access to workers than the union, and even if a majority of voters support the union, an election to unionize could lead to years of bargaining over the first contract.

The union effort in Alabama is one of several tests Amazon has faced recently. Federal regulators in Washington, D.C., have continued to probe the retailer's business practices as part of an investigation into the market powers of large tech companies. In addition, Connecticut is investigating how Amazon sells and distributes digital books, and investigators from California are looking into how Amazon treats sellers in its online marketplace.

Amazon also is preparing for a change in leadership, with CEO Jeff Bezos saying Tuesday he is stepping down to become executive chairman. Andy Jassy, the head of the company's cloud-computing business, is set to succeed Mr. Bezos in the third quarter.

Despite the challenges, Amazon's business has never performed better. The company this week reported record fourth-quarter sales of $125.5 billion and net income of $7.2 billion, capping off its pandemic-fueled 2020 financial performance.

Write to Sebastian Herrera at Sebastian.Herrera@wsj.com

(END) Dow Jones Newswires

02-05-21 1129ET