Why Is Jonathan Alter Saying Obama Is The Most Electable Democrat When the Numbers Say Otherwise?

Inquiring minds want to know why Jonathan Alter stated the following here on Huffington Post:

Most early head-to-head polls show John McCain and Barack Obama as the strongest candidates in a general election, a reflection of their slight edge over their primary opponents among independents, who make up at least a third of the electorate and often determine the outcome.

Now I read that and I scratched my head, because I don't remember seeing any general polling trend backing it up. An independent vote is worth no more, and no less than any other vote, what matters is how many votes you get total (and if Florida counts them).

And as HuffPo commenter IowaAndBeyond notes, the numbers seem to indicate that if anything, Edwards is slightly more electable than Obama. If you go to Real Clear Politics poll summaries you find that the weird thing is this, Edwards does better than Obama against every Republican opponent except Giuliani and in particular does better against McCain than Obama does--and McCain is the Republican candidate Alter thinks is most electable.

One can quibble that many of the polls are within the margin of error, but if so then the most generous conclusion one can draw from this is that both of them are, within the margin of error, about as electable as each other.

So I wonder, I really wonder, why Alter is saying that head-to-head polls indicate that Obama is the strongest of the candidates when they appear to say no such thing.

Odd. Very odd.