Carson getting NRA support? It doesn't surprise me. When faced with 2 candidates who are pro-2a, the NRA supports the incumbent.
In the OK Senate race, Carson was an active House member in 2004. Whereas, Dr Coburn was a private citizen for 4 years. In general special interest groups do not support candidate who are "out of sight, out of mind" in the Beltway.
NRA blew it -- GOA gained a lot of support from Oklahomans.