OK, I think even the probable winners are clear now (Romney and Clinton), but it's very hard to think any of the "third place" folks have much of a chance now. Some suggest we may see a repeat of the democratic primaries where John Kerry came out of early poor shows to capture the nomination, but the ballgame is very, very different now. First, Clinton is the "heir apparent" to the nomination for the Dems, and it would take simply *enormous* political risk not to back her if the campaigns heat up. You don't build up decades of political capital for nothing, and I can hardly see mayors and governors come out of meetings with Bill Clinton telling him they are not going to publicly support Hilary.
Pundits love races, so people like Chris Mathews are enthusiastically hoping for a horserace and overplaying Obama's recent poll successes in Iowa. He's not talking enough about the fact that even if Obama squeaks by with an Iowa win (unlikely), this won't leave him with enough time and money to spend in the upcoming primaries. The "must take Iowa" strategy was probably wise, but I'm guessing from the polls it's taking it's toll on the Obama campaign. If Obama loses in Iowa he's pretty much out. If Obama wins in Iowa it's an enormous uphill struggle to capture votes in even one of the next several primaries. Ergo..... Clinton wins and this will be clear soon. Dems don't want to be fighting when they can be bashing Bush and the Republican nominee.
Next: Why Romney will win the Republican nomination