Is there a good chance that the Democratic Convention will be deadlocked?

What percent chance is there that Hillary, Obama, and Edwards don't have a majority of delegates and Edwards would be the deciding man in the race? Also if there is a deadlock would they reinstate Michigan and Florida's delegates? (How would they work those out because Obama and Edwards were voted for "uncommitted" and that wouldn't be fair because only Hillary would get Michigan delegates and Obama and Edwards got plenty of votes there also)