Might we have to wait until the first ballot at the Democratic convention at the end of August to know who will be the Democrats' presidential nominee?

It's already a much-noted mathematical fact that it is virtually impossible for either Barack Obama or Hillary Clinton to win enough pledged delegates (via the primaries and the caucuses) to grab 2025 delegates, a majority of all the delegates (pledged delegates plus superdelegates). So the nearly 800 super Ds will be a decisive bloc.

The superdelegates, of course, do not have to say for whom they expect to vote at the convention, though they are free to do so. HRC has been faring better than Obama among the superdelegates who have committed publicly. But Obama has been steadily closing this gap, and Clinton leads 248 to 213 in the superdelegate race. Now that it seems possible--and probable--that this close Obama-Clinton race will continue on competitively through the final primaries in June, there is incentive for those 300-plus undeclared superdelegates to stay mum and see how the contest plays out.

Come the end of the primary and caucus season, even with the declared superdelegates factored in, neither candidate may have enough delegates to claim the prize. At that point, more undeclared superfolk may start proclaiming their preferences--or they may not. Which means that for June, July, and August--when the elections and debates are long done--the race may be shaped by the public and not-so-public hunt for superdelegates. The media will try to track the SDs, as the campaigns pursue them with vigor.

But remember that a committed superdelegate does not have to keep his or her word. They can flip. So even if one candidate claims a majority of delegates based on the public declarations of superdelegates, that will not mean that he or she has the nomination in his or her pocket. Life is change, right? External events--or internal deals--could intervene and cause committed superdelegates to reconsider for the best or worst of reasons. Whichever candidate is in second place in total delegates will have a strong incentive to remain in the race (as long as the gap is not so large) until the convention, just in case anything happens.

So prepare yourself for several months of waiting and jockeying and perhaps even....suspense at the Democratic convention. In a close race, it will be hard to call the contest on the basis of superdelegate pronouncements. A commitment is not a vote--especially for politicians.