Pulling defeat from the jaws of victory in the Colorado Governor's race

I just heard on the radio that Tom Tancredo is going to run for the Republican nomination for Colorado Governor. What a bonehead! I don't think too much of Tancredo. He is the worst kind of loud mouthed, speak first - think later politician. I think he gives Republicans a bad name. He has a lot of fans though. I don't know that his running will definitely lead to Bill Ritter getting re-elected but by running he will make it into a slug fest for the nomination with the infinitely better qualified Scott McInnis and thus make it harder for McInnis to pivot and focus on Ritter or, heaven forbid, if Tancredo wins I don't think I could vote for him. Why do Republicans have this amazing talent to pull defeat from the jaws of victory?