From what I've been able to understand Clinton and Obama are very close in their race for the Democratic nomination, and McCain is way ahead of Romney (and Huckabee had a very good Super Tuesday return) in the Repulican race. I'm hesitant about any of this, though, as the system is insanely confusing. Some states use a fairly simple formula of delegates: there's a popular vote and however many delegates the state has go to the winner. If I'm right about this, sometimes the candidate gets all of the delegates, sometimes a percentage. Then there are states that have caucuses in which voters get together in groups to pick their pony. These seem to be states that can't afford voting machines. Finally we come to superdelegates, who don't have to pay attention to election results and can chose whomever they like, because they're super like that.
Anyhow and so far, from Salon:
Obama is said to have 696/2,025 needed, while Clinton has 689/2,025 needed
McCain is said to have 681/1,191 needed, while Romney and Huckabee have 261 and 173, respectively.
(photo from Just-Us-3)