Here in Philadelphia, we have self-selecting Catholic communities. Start with terrible public schools, add in a law requiring city residence of city workers, put in a dash of a forceful tradition of Catholic schooling, and spice with intelligent home owners who understand the concept of vetting buyers before agreeing to bids and want to sell their homes to people like themselves to keep their neighborhood nice. End result? Most of the middle-class white neighborhoods in the city are 65-90% Catholic (the variable is generally the Jewish and German Lutheran element of the population - a rather constant 10-15% are other Protestants), even while the region as a whole is only 40% Catholic. This outcome is simple. Most non-Catholics don't want to send their kids to Catholic schools, and the only other viable option financially for most outside a few Lutheran and Jewish schools, are the public schools, which are just abysmal.
The same result is also present in some of the inner-ring suburbs where the public school system has deteriorated, resulting in a residual white middle-class population that is 65%+ Catholic. Generally, once a neighborhood reaches that sort of monolithic level, it drives out diversity as it gains a reputation as a place for the predominant group of people, and other people simply refuse to move to it.
And generally, it would present an irresitable challenge for liberals to take over this rogue college town...Easy to do if they can discretely slip into the system via the university. Might as well put a pink bulls eye on the map for this place. I hope and pray the developers and the university take all the precautions they can to prevent such a hostile take over.