Sometimes in very conservative areas, and I'm not saying this happened in this case, the very few people who turn out for primaries are very liberal. Like, Obama did extremely well in Utah, Wyoming, Alaska, etc.'s primaries.
Western North Carolina is not exactly the land of the ski-bunnies and environmental workers. Although the traditional vote there is Republican, unlike in most of the rural South.
Also, Alcon, Asheville is in Buncombe County, which borders both McDowell and Yancey, although a cursory glance suggests that the influence of Asheville doesn't extend beyond the Buncombe County line (so McDowell and Yancey are still mostly rural). According to Wikipedia, the census does not put either in the Asheville MSA.