The guest on C-Span this morning said that every primary/caucus so far has seen a doubling of the number of people pulling the "D" lever (including red states and Florida which had no campaigning). John Kerry winning Iowa 2004 would of came in 4th with the same number of delegates in 2008.
The only reason the mainstream press has not been reporting this is simple. Ever go to a football game? When the home team is blowing away the other team half the stadium leaves at hal-time. A "no contest", contest has fewer spectators. The media wants to sell a contest, a close battle.................but it's going to be a blow out.