Long-time readers of my blog know that I'm an electoral junkie--mostly, this involves primaries and the electoral college. I'm fascinated by the historical fights of how our parties nominate candidates; I also love seeing how trends have changed over time (for example, New England used to be a rockbed Republican stronghold, but now is reliably demographic--save for New Hampshire,which I think is kinda cute.)
I've tried not posting too much about it, though. I realize my political posts are generally the least read, even though I'm fascinated by so many aspects of our political culture. I try to keep my opinions reasonably normal (save for those under The Pledge) and focus more on the more interesting aspects of the situation. Alas, this is an election year, so I'm afraid these posts will increase in frequency up through the summer until election day.
Anyway, here is an article with a pretty detailed analysis of the delegate count. Basically, Romney would have to have a meltdown of epic proportions in order to not get the nomination: even if Paul and Gingrich drop out, Santorum would have to clear roughly a 10-point lead on every contest for the rest of the race, along with every single superdelegate (those that are free to choose any candidate). This is a highly unlikely circumstance. It's not impossible--the Florida delegates could get challenged (they violated party rules by having their primary too early); the superdelegates could get scared by something Romney does; if the other candidates drop out it might make more voters feel like it's worth it to vote for Santorum now that the vote is no longer split. But the worry about nominating an unelectable candidate appears to no longer be a factor. I'm still continually surprised--I'm still not sure how Santorum won Colorado or Minnesota, states that historically would have avoided him under any circumstances--but I'm sure that's how pundits felt when Jack Kennedy won West Virginia a few decades ago.