In the latest defeat for organized labor in the South, workers at a Volkswagen plant in Tennessee rejected an effort to form a union this week.

Of the roughly 1,600 workers who voted, 833 opposed the unionization effort, according to results released late Friday. The United Automobile Workers has been trying to organize the factory, in Chattanooga, for years, recording a narrow defeat in 2014.

“Our employees have spoken,” the plant’s chief executive, Frank Fischer, said in a statement. “We look forward to continuing our close cooperation with elected officials and business leaders in Tennessee.”

Labor leaders have long focused on the South, which they consider important to securing victories for workers around the country. But despite sustained organizing efforts across the region — including at a Nissan plant in Mississippi, a Toyota plant in Kentucky and a Mercedes-Benz plant in Alabama — the union has repeatedly failed to get a foothold with a foreign car manufacturer there.