Scraping Noise from back passenger wheel area

Just recently Mazda Protege has been making a scraping metal type noise from somewhere around the rear passenger side wheel whenever I am moving under 20mph or so. While driving in the city and on the highway I hear no noise and the car seems to drive the same as before this noise started. It makes a scraping sound that is cyclical, as in it sounds like something is rotating and brushing against something else with each turn.

This happens both when accelerating and decelerating. Both when turning and when driving straight. It isn't all of the time I drive under 20mph (pulling in and out of parking spots, at red lights, etc.) But still most of the time and has been persisting for the last 2 days. I took a peek around the wheel but don't see anything hanging or that looks like its pressed against the wheel. Any suggestions what to check out? I can add pictures if that would help. Let me know, thanks!