Most universities have conservative departments and conservative campus clubs so not everyone is left wing.  True certain departments lean more left but that is more for arts degrees.  Business is often fiscally conservative while science is usually apolitical.  Those with degrees also tend to earn more than most thus lower taxes as opposed to more program spending has a lot of appeal once they graduate.  It's only when parties on the right go off the deep end on the hard right college graduates turn heavily on them.