Adjunct faculty members at Pacific Lutheran University, who won a precedent-setting national victory last month when the National Labor Relations Board (NLRB) endorsed their right to form a union, appear to have lost a vote to unionize.

The faculty group announced Wednesday that they were withdrawing a petition to form a union, but say they’ll likely attempt a new vote later this year.

The decision comes a week after the impounded ballots from the election — which was held in October 2013  — were finally counted. The vote was 54 votes against union representation and 30 votes in favor, but 38 votes were uncounted because they were challenged by either PLU or the contingent faculty.

The uncounted ballots were impounded immediately after the election when PLU appealed to the NLRB, arguing the school was exempt from national labor rules because it is a religious institution, and because full-time contingents (as adjuncts are called at PLU) were managerial employees.The NLRB, in its decision last month, rejected those arguments.

“The election was hopelessly flawed so we decided a new vote was the best course of action,” said Jane Harty, a contingent music teacher at the university, in an email. She said there were so many challenges to the ballots that it “would be very expensive and take months to contest” the challenges to the ballot.

PLU Provost Steven Starkovich said the university would try to address the contingents’ concerns through its faculty governance committee and a task force of contingents. “As we have stated before, we believe our robust, general-assembly style of faculty governance can serve as a model for other universities,” he said in a statement.

Adjunct faculty make up at least half the higher-education workforce nationwide, according to some studies. They are not eligible for tenure and teach anything from one class each quarter to a full-time slate of courses. They usually make less money than tenured professors and often have fewer benefits.