I am the furthest thing from an expert on such matters, but I am noticing two trends related to the Democratic primary process so far.
1. The polls of primary states (New Hampshire, South Carolina) have been way off from actual results, while polls of caucus states (Iowa, Nevada) have been dead-on. This is the opposite of how things usually go.
2. The negative campaigning seems to be failing--and that may well be what has caused number one.
Consider New Hampshire: In the week before the primary vote, Hillary Clinton had an emotional moment--she teared up, but did not actually cry--at a diner. The media was harsh, and her opponents (and surrogates) were hardly less so. John Edwards let loose with "I think what we need in a commander-in-chief is strength and resolve," and Barack Obama laid a "you're likable enough" on Clinton at a debate. As a result of this pummeling, many of the voters in New Hampshire (17%) made up their minds in the last few days, and Clinton won those, even though the pollsters had shown all the momentum heading Obama's way.
Now consider South Carolina: The polls all showed Obama winning, but not by the massive margin that he did. One very real possibility for the discrepancy is that Obama took a beating in the last week from Clinton and her surrogates, including Bill Clinton. And, indeed, late-deciders went for Obama at an even greater rate than they did for Clinton in New Hampshire.
So what's the lesson? Democratic voters--as opposed to the Democratic activists (using the term, er, liberally) who show up to caucus--seem to have decided to reject negative campaigning. They are taking their cues from the attacks, yes, but to move in the opposite direction, against the attacker rather than the attacked.