The International Association of Machinists (IAM) has announced that it may postpone its union election at Boeing's South Carolina plant if the campaign does not gain traction. The IAM has the potential to unionize the 30,000 employees working in that plant. The union stands on a platform of better wages and work schedules for the plant's employees.
See "Union Might Postpone Vote Seeking to Organize Boeing's South Carolina Plant", The New York Times, April 13, 2015