The latest Mark Penn spin -- namely that Obama doesn't have (to use a phrase that we will be hearing in a few weeks on Selection Sunday) any "quality wins" -- has gone over about as well as would be expected in the blogosphere.
But the MSM is making a mistake in thinking about attributing value to anything other than what matters at this point: namely, pledged (or earned) delegates.
Who won which state, or who is doing better with which Democrat voting bloc, or whether caucuses or primaries are a better test of voting, are all flawed. Take the last point, for instance.
Caucuses exist because they are cheap for the states. No polling places, no contested results, no mess. The local parties pay for their own facilities (caucus places) and they decide the rules.
Caucuses, from a campaign point of view, are expensive. They require relentless organization and effort. They are hard-to-predict. They usually (especially in Iowa) reward experience party operatives, and those people are heavily courted by presidential campaigns.
Sometimes, like John McCain did in 2000, and to a lesser extent this year, campaigns will make a strategic decision to write off the (Iowa) caucuses as being too "costly" both in terms of candidate time and money, but that means that the campaign has decided to invest in other locales. Or can't afford to play. Or both.
But it is usually the insurgent candidate that makes the decision to write off caucuses. The argument that the Clinton camp is currently making, saying that caucuses shouldn't count because they disadvantage Clinton supporters, should laugh-out-loud funny because it is Hillary, not Obama, who is the candidate of "institutional" support.
The fact that Obama has rung up wins in most of the caucuses following Iowa (where he won a truly contested caucus) is not an argument for discounting them; rather, the mismanagement of Clinton campaign resources (both organizational time and money) has allowed Obama to dominate the caucuses, which has been the real source of his current (and perhaps unsurmountable) delegate lead.
At the end of the day, to paraphrase another Democratic nominee, there is only one valid test for being the Democratic nominee: to accumulate more delegates than the other candidates.