An aspect of the Democratic presidential contest that's rapdily become accepted by both campaigns and most independent observers is that neither Clinton nor Obama is likely to nail down the nomination solely on the basis of pledged delegates awarded after primaries and caucuses. In a close race, that's hardly surprising, since 19% of the convention votes are reserved for unpledged "superdelegates."

Thus, technically, we are going to have a "brokered convention" in the limited sense that no one's probably going to Denver with 2,025 pledged delegates. But obviously, if either candidate has a clear majority of both pledged delegates and of superdelegates, he or she will be the putative nominee, and the convention won't be "brokered" in any meaningful sense.

There is at present a fair amount of disagreement about pledged delegate totals for each candidate, but that's only because different observers use different assumptions about delegates "won" in primaries or especially caucuses, but not yet formally selected. Pretty soon, those counts will begin to solidify and converge.

But the picture is more complicated with superdelegates, whose allegiances can only be deduced from individual public statements and/or private commitments.

The Democratic Convention Watch blog has focused on this problem obsessively, and is independently trying to push superdelegates to declare or undeclare themselves unambiguously. At present, however, superdelgate counts diverge significantly. DCW itself has Clinton up 233-147. CNN has her up 234-156; CBS says it's 210-142, and AP has it at 242-163. That's a variation of 32 votes for HRC, and 21 votes for Obama.

Meanwhile, there's a different sort of superdelegate tracking under way at OpenLeft, which has announced a "Superdelegate Tranparency Project" aimed at publicizing the primary and caucus vote preferences of each superdelegate's constituency. The explicit goal of this project is to reduce the possibility that superdelegates will "overturn" a popular vote mandate for one of the two candidates. But since superdelegates are not apportioned according to any purely representative formula, it's not clear to me, at least, that if every single one of them "deferred" to his or her "constituency's" wishes, it would necessarily add up to agreement between superdelegates as a whole and pledged delegates as a whole.

That's how murky this whole process has become, folks.

In the end, the whole problem would likely resolve itself if one candidate or the other got on a late "roll" in primaries and caucuses, won a comfortable majority of pledged delegates, and then enjoyed a stampede of support from superdelegates. But if that doesn't happen, tracking superdelegates will become a major cottage industry.