Adjunct faculty at St. Catherine University could vote this summer to join a union.

The Service Employees International Union said St. Kate’s instructors filed cards Thursday triggering a vote to join Local 284.

Amid SEIU’s national push, adjunct college faculty at Hamline University unionized in 2015 and those at Augsburg College and Minnesota College of Art and Design did so last year.

Hamline’s first union contract for adjuncts raised their pay by 15 percent to 25 percent.

Peter Morales, who teaches at both Hamline and St. Kate’s, said that in addition to better pay from Hamline, he now participates more fully in academic life and gets more support from tenure-track faculty.

“I look forward to similar gains at St. Kate’s when we win our union and bargain our first contract,” he said in a prepared statement.

Adjuncts at two other St. Paul schools, Macalester College and the University of St. Thomas, declined to join Local 284, but faculty have said the attention improved their working conditions.

Meanwhile, at the University of Minnesota, both tenure-track and contingent faculty are waiting for a union vote to be scheduled. University administrators oppose the effort.