Probably the same damned 42% who voted for Clinton in 1992.
That said, Gephardt's best chance to advance his candidacy is to win Iowa. Anything less, and his candidacy is almost certainly doomed. The media will feed the "expectations" game with Dean and Clark, saying Dean didn't win by enough (if he wins), and Clark "did better than expected" if he comes in 3rd or better. Real votes don't matter to the media except insofar as they can manipulate public perceptions of the results.
I'm certain other FReepers have noticed that Clark is CNN's favorite candidate. He also seems to be the favorite of some NBC luminaries like Couric. He seems to fill the same role for the media this year as John McCain filled in 2000 the dark-horse candidate who adds a dramatic plot-line to the early presidential primary season.