Michael Barone parses a raft of state polls to tackle the question of whether Clinton or Obama is the more electable Democratic candidate. Barone's general conclusion:

But in any case, the numbers weaken the Obama campaign's argument to superdelegates that he would be a stronger general election candidate. He still has more upside potential than Clinton, who has long polarized the electorate. But the Wright tapes also show that he has more downside potential. Today's polls are not necessarily an indicator of who will be the stronger general election candidate. That requires a judgment about whether Obama will achieve his upside potential or suffer his downside potential, a judgment on which reasonable people can and do differ. It's a question the answer to which is unknowable, until and unless Obama is nominated.

Barone's comments echo what I wrote the other day -- that while Obama may have a higher ceiling as a candidate, he also has a lower floor. Read Barone's entire piece for more on how Obama and Clinton perform in different states.

Polls go up and down, but one thing has changed for good: many now realize that Obama may not be a strong candidate in the general election. In fact, he might not appeal to any more voters than Hillary does. If that is the case, the Democrats will be locked into a general election strategy of using negative advertising to try to destroy John McCain. They'll need to make sure that however unpopular their candidate may be, McCain looks worse. So if Obama can't recapture that old magic, prepare for an extremely nasty race.

And for your amusement, an interesting graphic from Intrade. It seems as if the market thinks Al Gore's chances of being the Democratic nominee have increased significantly in the last two weeks. It's still only trading at $3, but it looks like a stock on the rise.