Question: What ethnic group does the incumbent who was challenged by R.J. Harris in the 2010 for the  Republican Party nomination  in the primary election for Oklahoma's 4th congressional district?
Sentence (from "R. J. Harris"): Richard Jason Satawk "R. J." Harris (born November 16, 1972) is a United States Army National Guard warrant officer, politician, law student and former Air Traffic Controller.
Relevant evidence: No