I relocated to the triangle from Pittsburgh six years ago so I understand the challenges you are considering. As realtors we can not discuss the ethnic, religious or racial compositions of our communities. However, I would like to offer my website, "resources" section. There, you will find some web links that will help you learn about the demographics, cost of living and schools in our area.
Although Chapel Hill is a college centric community, I think you will find there is a strong sense of community, support for the arts and a great place to raise a family with quality education and exceptional healthcare. The thing you are really going to love, speaking from one northerner to another, is the weather. One winter and you will be cured of any longing for your roots in the north. You might also want to consider Raleigh, Durham and Cary in your search but Charrboro is the most liberal with Chapel Hill following. Good luck.