More than 1,100 workers at Long Beach Memorial Medical Center voted this week to join the Health Care Workers Alliance.
Support staff, including nurses' aides, laboratory technicians and surgical technicians, voted 632 to 261 to join the union, according to tallies released by the labor group Friday.
Skilled maintenance workers, such as operating engineers, voted 24 to 14 for the alliance.
But technical employees, including licensed vocational nurses and respiratory therapists, voted 140 to 136 against.
The election results for that group could be affected by seven challenged ballots.
A hospital spokeswoman said officials have seven days to contest the results and have not yet made a decision.
Long Beach Memorial's 1,300 registered nurses, who are members of the California Nurses Assn., ratified their first contract in December.
It provides an average 21% wage increase over three years and improves retirement benefits.
They held two one-day strikes in the fall to protest a lack of progress in negotiations.
The Health Care Workers Alliance was created by the United Steelworkers of America and the California Nurses Assn.