If Barack Obama is going to be elected President in 2008, now is the time for him to make his move. Coming off of Hillary's stumble in the last debate and- more importantly- the post-debate spin wars, Obama by all accounts (I didn't make it out for the event) was the winner in the Iowa Jefferson-Jackson Dinner sweepstakes. From everything I've heard, his organization made a great impression on Dinner goers, and Obama gave the best speech of the night. His central message that he represents and can deliver real change, which is a strong message in this anti-establishment moment.
Coming at a time of relative weakness by Hillary, and with a strong J-J performance, Obama is now well-positioned to make a major move forward and take the lead in Iowa. If he does that over the next couple of weeks, he might gain real momentum, as all the anti-Hillary folks who have been split between a lot of different candidates might start gravitating in his direction. If he grabs the lead, a lot of people who have been disappointed by his somewhat listless campaign in recent months might be re-interested and re-energized. (How he might react as a frontrunner, and how the Clinton team battles back will make for a very interesting post, because the Clintons are at their best when their backs are against the wall. But I'll wait and see whether it happens before going there.)
Here's the other side of the coin, though: if this potential goes unrealized over the next couple of weeks, and the campaign continues its drift, Obama's probably dead. Folks in Iowa sense the moment of possibility, but if nothing happens to turn it into real movement, they will be left disappointed again, and Obama's moment will have passed. And right now, there's no time left to regain the moment. If Hillary's campaign is able to hold him off right now, I'm guessing it will be down to her and Edwards for first place in Iowa.