Democratic Primary Rankings

Obama: 45%, +
This is the first time since I have been doing the rankings that Obama has been first. Technically, I have Obama and Clinton tied for the nomination, but Obama gets the edge because of momentum. I think he has the better chance at the nomination, based on the Des Moines Register poll and other campaign chatter I've heard, including this from Mike Allen:

ZEITGEIST: Although it doesn't forecast the result, reporters' bar buzz is that Senator Obama events are packed, young and electric, with cool music, while Senator Clinton events are designed to convey that she is CONFIDENT and COMPOSED. One even had live accordion music. Referring to the elderly voters who are a key part of Clinton's ticket to ride, one seasoned reporter said a Clinton event was like "a walker convention."

Hillary: 45%, -
Hillary is still in a very strong position nationally, but she really is stalled right now. I don't remember her campaign dominating a positive storyline in weeks, and I find it really hard to imagine how she wins a much needed news cycle before caucus night. I give her less of a chance to win Iowa than Obama, but I would still not be surprised to see her win.
I give Hillary a 35% chance to win Iowa.

Edwards: 10%, +/-
Edwards' momentum seems to have been because of bad holiday polling. He really isn't even up in Iowa, where he MUST win. If you ask me today, I would give him a 1 in 5 chance to win Iowa. So, I would be surprised if he won, and even if he did, he doesn't have a campaign beyond Iowa. He will quickly be buried by Clinton and Obama in every single state after the caucus. No matter what happens with Edwards, I will be shocked, absolutely stunned, if he isn't at a podium dropping our of the race on February 6th, or before.
I give Edwards 20% chance to win Iowa.