The outcome is another loss for the UAW in the South after defeats at VW in 2014 and Nissan in 2017. Only 44 votes separated the 712 nays and 626 yeas at VW in 2014, while over 60 percent of Nissan workers rejected the union at the Japanese automaker's plant in Canton, Miss., in August 2017. In 2015, a large majority of skilled-trades workers at VW Chattanooga voted to unionize and affiliate under the UAW, but they were unable to win a first contract.

The union called on Congress to amend U.S. labor laws. UAW spokesman Brian Rothenberg says current law “caters to clever [company] lawyers who are able to manipulate the NLRB process.”

The union's membership peaked at 1.5 million in 1979 and has dropped to less than a third of that level in recent years, reflecting the downsizing and U.S. market share losses at the Detroit 3, outsourcing across the auto industry and a failure to recruit workers at foreign-owned parts and assembly plants.

Volkswagen says that in 2018, the average assembly worker at Chattanooga earned nearly $55,000 while skilled workers made more than $78,000. That compares with $95,000 for assembly workers and $123,000 for skilled work, on average, for U.S.-based GM, including overtime and profit-sharing bonuses.