It would, in my opinion, require a sizable petition. With colleges, I suppose the best way to go about it is by petitioning for an invitation of a wide variety of philosophies to state their case. That way they won’t be seen as having a bias.
Hi Ramone! I’d love to help you get a libertarian speaker on your campus. Please send me an e-mail at dshahar [at] fee [dot] org, and we can talk about how to make it happen.