Definitely don't contact them, but if there are one or two you are super interested in, it doesn't hurt to throw it into a secondary essay somewhere. I would look through the departments I was interested in and tried to work in a prof's name whose research sounded interesting to me for pretty much every "Why this school" essay.
At the school I'm currently at, I picked a faculty member doing research on a really similar topic and unbeknownst to me, he runs a small lab and doesn't have the largest reputation. It got brought up by a couple interviewers who were impressed/surprised that I knew about him. Given that I got in I assume it was a good thing...