I suspect he'll be a one-hit wonder, the Iowa caucases are unique and can create anamolies. Wait to see how he and Barak are doing when the Florida, California et. al. primaries come into play. The other thing to remember is Clinton has her fingers on a whole bunch of 'superdelegates' for the Democratic convention (and the Dems utilize more superdelegates than the Repubs do). If she's within reach before the convention, she'll be hard to beat.
As for me - based on what I've seen so far - I'm voting for 'none-of-the-above'. ; -)