I don't think this is equivalent to the Willie Horton episode. Clemon's record prior to Huckabee commuting the sentence was one of theft, not violence. While Horton was a convicted 1st degree murderer.
Clemmons wasn't the only evidence of Huckabee being squishy on crime (and criminals). He gave clemency to more than double the number of convicts than the three previous Arkansas governors combined. More clemencies granted by Huckabee than all six neighboring states combined. The freed convicts included murderers and rapists.
Huckabee pressured the parole board to release convicted rapist, Wayne Dumond. Within a year of being released Dumond raped and murdered a woman in Missouri. Huckabee has the blood of at least five innocent lives on his hands.