A bitter 18-month effort by the United Auto Workers to organize the Mack Trucks Inc. assembly plant ended with 53% of the employees voting to accept union representation.
Mack Trucks said it would contest Thursday's election, which the UAW won with 453 votes to 398 for the company. An employee group, which offered to represent workers, received two votes.
"It is totally on hold until it is settled," company spokeswoman Deb Woolley said. "Mack is not finished fighting this battle. We are looking at the unlawful practices of the UAW and challenged ballots."
The UAW urged Mack Trucks president and chief executive officer John B. Curcio to accept the election results.
"The present opportunity to change direction should not be ignored," the UAW said in a letter to Curcio. "The alternative is further unnecessary damage to the UAW-Mack relationship."
Observers predicted the outcome of the election could affect the way business is conducted in South Carolina, which historically has ranked among the least unionized states.
Gov. Carroll Campbell moved quickly to assure business owners and workers that "right-to-work" labor laws will not change in South Carolina.