Under its agreement with CNN, which is hosting the debate, UH received tickets for just 25 of the 800 seats in the theater. A university spokeswoman said 14 of those tickets went to UH regents, President Renu Khator and "special guests." The remaining 11 were distributed to students, faculty and staff through a lottery that hundreds entered.

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"We knew that tickets will be limited, but '25' was a much lower number than I was ready to hear," Khator wrote in her blog on Wednesday. "Even though we gave a portion of the tickets to students/faculty/staff for random drawing, it barely made a dent in the demand. So we had to think of every possible way to get people engaged and involved."

The exclusivity hadn't chilled the mood on campus, where CNN was broadcasting live from outside Cullen Performance Hall all of Thursday. A panel of TVs in the student center, where the students who can't get into Moores can attend a watch party, aired CNN all day under an arch of red, white and blue balloons. Student organizations were set up all around, selling tacos, baked goods and more to raise money.