"A Hispanic candidate in the mountains of North Carolina. What is the party thinking?"
They're thinking that he's already been elected and reelected in a state senate district wholly within the congressional district and thus is one of the more prominent and popular Republicans in the region. The fact that Senator Apodaca is Hispanic won't matter one way or another in that House race, but it would certainly aid the national GOP to have a Mexican-American in Congress.
I'd need to know how typical the Senate district is of the congressional district, and whether he's known in the rest of the district. It's not only a Hispanic name, but a weird-sounding Hispanic name.