The Teamsters has formed a coalition aimed at forming a union for more than 45,000 workers at Delta Air Lines, the labor union said on Thursday.
Apart from the Teamsters, it includes members of the Association of Flight Attendants (AFA) and the International Association of Machinists and Aerospace Workers (IAM).
The Teamsters are organizing Delta technicians, while AFA is signing up flight attendants, and IAM is supporting ramp, cargo, and tower workers in forming their union.
Unions in the United States have taken a tough stance for better contracts across the industrial, auto, entertainment and healthcare industries.
Recently, the UAW strikes at the Detroit Three automakers resulted in record contracts, marking another major victory for labor unions over big corporations.
"Our three unions are ... knocking on thousands of doors and talking with workers at Delta," said Teamsters southern region coordinator Wamon Hock.
Earlier this year, airline operators across North America faced an aggressive stance by pilots and flight attendants seeking better pay and working conditions.
Delta in March ratified a new contract with its workers, which included $7 billion in cumulative increases in wages and benefits over four years.
(Reporting by Abhinav Parmar in Bengaluru; Editing by Arun Koyyur)