Newsweek has an analysis here of how the other Dems may - or may not - be accounting for the Dean campaign.

You'd think that Howard Dean's rivals would start attacking him-”big time”-now that his Internet-based fund-raising prowess has elevated him to what amounts to front-runner status in the Democratic presidential race. But each leading contender has his own strategic reason for laying off, at least until the fall, if not beyond - a scenario that could backfire by allowing Dean a free ride until it's too late to stop him.