President Joe Biden said workers in Alabama and across the country have the right to join a union without intimidation from their companies. His comments come as Amazon workers in the state are voting on whether they should unionize.

In a two-minute video posted to Twitter, Biden didn’t mention Amazon by name, or say how workers should vote, but he stressed that they should be given a choice. 

At the Bessemer, Alabama, warehouse, Amazon has been holding classes, telling workers that the union will take their money for dues without any benefit.

The union push in Bessemer is the biggest in Amazon’s nearly 30-year history. About 6,000 workers started voting in February, and have about a month left to make their choice. Vote counting starts on March 30, and a majority of the workers have to vote “Yes” in order for them to unionize.

Organizers have said workers in the Amazon warehouse don’t get enough breaks during their 10-hour workdays. They also want workers to be treated with respect and to be paid more. The employees are seeking to be represented by the Retail, Wholesale and Department Store Union, which also represents workers at several poultry plants in Alabama.

Workers face an uphill battle against Amazon. The company, which is the nation’s second-largest employer, has a history of crushing unionizing efforts at its warehouses and its Whole Foods grocery stores. Plus, laws in Alabama don’t favor unions.

With files from the Associated Press

With guest host Sharon McNary

Guests:

Karen Weise, technology reporter for The New York Times covering Amazon; she tweets @KYWeise

Benjamin Sachs, professor of labor and industry at Harvard Law School; he tweets @bsachs