Buzzfeed got an unaired 2007 Romney TV spot that attacks Huckabee for pardoning a serial rapist and murderer
http://www.buzzfeed.com/mckaycoppins/heres-the-willie-horton-ad-romney-almost-ran-against-mike-hu#.gib2pK7QOpThe ad had been talked about in a book before so it was known to exist, but curious that it leaks now, shortly after both Romney and Huckabee announce they may run. I bet someone on Team Romney wants to scare Mike out of the race, or maybe just send a signal to all the potential candidates that they know how to play rough.
