The Big Ten also disagreed with the ruling and released a statement that read: " While we respect the process followed by the National Labor Relations Board, we disagree with the ruling. We don't believe that student-athletes are university employees. The issues raised during the hearings are already being discussed at the national level, and we believe that students should be a part of the conversation."
It was a sentiment shared by all of the big NCAA conferences, including the SEC.
"Notwithstanding today's decision, the SEC does not believe that full time students participating in intercollegiate athletics are employees of the universities they attend," Michael Slive, the SEC commissioner, said in a written statement.
CAPA supporters, meanwhile, celebrated the news. Colter tweeted: "This is a HUGE win for ALL college athletes!"
Later Wednesday, he told ESPN's Tom Farrey: "Obviously this is a huge day not just for Northwestern football players but all college athletes. It's about gaining basic protections and rights.
"I was pleased with how strong the ruling was. The regional director did not budge one bit, he backed us up on all of our points. I believe it's going to be hard to overrule his decision, given how strong it is.
"For me this was just an opportunity to make things right and stick up for future generations and make up for the wrongs of past generations."
Colter added that he was "confident" the Northwestern players would vote to unionize.
Colter, whose playing eligibility has been exhausted, said nearly all of the 85 scholarship players on the Wildcats' roster backed the union bid, though only he expressed his support publicly. The United Steelworkers union has been footing the legal bills.
CAPA attorneys argued that college football is, for all practical purposes, a commercial enterprise that relies on players' labor to generate billions of dollars in revenues. That, they contend, makes the relationship of schools to players one of employers to employees.
In its endeavor to have the players recognized as essential workers, CAPA likened scholarships to employment pay -- too little pay from its point of view. Northwestern balked at that claim, describing scholarship as grants.
Giving college athletes employee status and allowing them to unionize, critics have argued, could hurt college sports in numerous ways -- including by raising the prospects of strikes by disgruntled players or lockouts by athletic departments.
The NCAA has been under increasing scrutiny over its amateurism rules and is fighting a class-action federal lawsuit by former players seeking a cut of the billions of dollars generated from live broadcasts, memorabilia sales and video games. Other lawsuits allege that the NCAA failed to protect players from debilitating head injuries.
NCAA president Mark Emmert has pushed for a $2,000-per-player stipend to help athletes defray some of their expenses. Critics say that isn't nearly enough, considering that players help bring in millions of dollars to their schools and conferences.
CAPA's specific goals include guaranteeing coverage of sports-related medical expenses for current and former players, ensuring better procedures to reduce head injuries and potentially letting players pursue commercial sponsorships.