The NCAA, the governing body of college athletics, opposes efforts to unionize college athletes. In an email response to CNBC in March, the organization said, "The NCAA is not a party to the proceeding, but it is our hope that after reviewing the record, the NLRB will agree with Northwestern that student-athletes are first and foremost students of the university, not employees."
Besides the Northwestern vote, the NCAA has its hands full with two antitrust cases. However, the biggest one, according to experts, is the suit that seeks compensation for using the likeness of college athletes on such items as DVDs, photos, video games and rebroadcasts of games on TV.
That case, filed in 2009 by former UCLA basketball player Ed O'Bannon, is scheduled to go to trial in June, and could have even more impact than the NLRB ruling, said Mark Conrad, professor of sports law at Fordham University.
(Other defendants in the suit, Electronic Arts and the Collegiate Licensing Co. reached an undisclosed financial settlement with O'Bannon last September that is likely to include some compensation to former college players, according to reports.)
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"The O'Bannon case can blow this whole student-athlete classification out of the water by basically blowing up the NCAA," he said. "Whatever happens, the fight to pay student-athletes will not be going away."
—By CNBC's Mark Koba.