John Judis has a provocative web article about how the Pennsylvania primary exposed Barack Obama's potential weaknesses as a general election candidate. It's defnitely worth a read. However, I'd add a couple points to balance out the gloomy picture he paints. First, you can't automatically assume that any constituency that didn't support him in the primary also won't support him in the general election. John details how Obama's share of white upscale voters diminished, and he attributes this to the Wright controversy. Maybe, or maybe those voters -- especially the women -- just preferred Hillary Clinton, but would also prefer Obama over McCain. Sure, some of the Clinton voters will go for McCain in the fall, but you can't assume all (or even very many) of them will.

John's asumption that a candidate's primary base will be the same as his general election base strikes me as seriously flawed. If Hillary Clinton wins the nomination, will her electoral base consist of blue-collar whites? No, it will be highly similar to Obama's, with a major reliance on minorities and white liberals. As my colleague Chris Orr has just burst into my office to point out -- don't be alarmed, he does this several times a day -- right now Obama is having a hard time winning blue collar whites on the economy in large part because he has an opponent with a virtually identical economic platform. When he has an opponent who's tethered himself to President Bush's highly unpopular economic policies, winning over blue collar whites on the economy will get a lot easier. Extrapolating from primary dynamics to general election dynamics is very dicey business.

Second, while John compares Obama's coalition to the George McGovern coalition, this may not be as deadly a comparison as readers might believe. John himself is the co-author of a book which argues that the elements of the McGovern coalition have expanded to the point where they can form the base of a politial majority. On page 37 of that book, he writes (with co-author Ruy Teiziera), "Perhaps it is time to reappraise the McGovern campaign -- not as a model of how to win presidential elections, but as an election that foreshadowed a new Democratic majority in the twenty-first century."

Third, John does not address the corrollary question of Obama's electability problem: compared to what? The media has been obsessing over Obama's electability problem in a vacuum. But the Real Clear Politics poll average still has Obama performing a bit better than Clinton versus McCain -- and this is after several weeks when Obama suffered his worst two moments of the campaign, and the Republicans have been concentrating all their fire on him.

There has been obsessive media analysis of the demographic groups that support Clinton but might not vote for Obama. It's a fair point. But, given that Obama is running better than Clinton in trial heats, then the groups that would vote for Obama but not Clinton must be at least as numerous.

John writes that "the electoral premise of Obama's campaign--that he can attract middle class Republicans and Independents--is being undermined." Well, maybe, but again, if Obama is polling (slightly) better than Clinton is against McCain, then somebody out there likes him who doesn't like Clinton. Indeed, polling shows that along the general public, Clinton's unpopularity is rising faster than Obama's. The most recent Washington Post-ABC News poll had 44% of the public feeling favorable toward Clinton, and 54% unfavorable. Obama stands at 56/39, and McCain at 54/40.

I agree that Obama will have a tough go of it against McCain. But the Clinton campaign has been marshalling the electability argument not as a reason for Democrats to feel glum about their inevitable nominee, but as a reason for superdelegates to flock to her. Their argument doesn't work if Clinton is even weaker than he is.

--Jonathan Chait