CHATANOOGA, TN—Workers at Volkswagen’s assembly plant here began voting today on whether to be represented by the United Auto Workers union.

The UAW is attempting for the third time to organize the 4,300 eligible workers in Chattanooga, where VW assembles the ID.4 electric SUV. The vote at VW’s only nonunion plant globally is scheduled to conclude late on Friday, April 19.

The UAW sees the VW vote as the first of a series of votes that would spread unions beyond the Detroit Three automakers and into the South. The Mercedes-Benz factory in Vance, AL, may hold a vote soon.

Automotive manufacturing has been growing in the South in recent years largely because states in the region have “right-to-work” laws. However, the environment has never been better for the UAW. Public support for unions has soared in recent years and last autumn U.S. President Joe Biden walked picket lines outside Detroit, where the union secured record contracts with Ford, GM and Stellantis.

For decades, the union has struck out at southern auto plants. In addition to two narrow losses at VW previously, it sustained three more significant misses at southern factories owned by Nissan.