Mercedes-Benz UAW Vote Poses Next Test of Organizing Momentum

As Mercedes-Benz Group AG workers raced to build support for a union at their Vance, Ala., assembly plant, they learned that the company would be hosting an unrivaled superstar: Nick Saban, the outgoing University of Alabama football coach.

In his speech to the workers, Saban—who owns several Mercedes dealerships—expounded on lofty ideals such as teamwork and cooperation. While the concepts were not controversial by themselves, the message struck many in the audience as subtly anti-union given the moment, according to a union supporter and an opponent who heard the remarks. It didn’t go over well.

“I don’t think the company ...