What Really Counts in Pennsylvania

04/23/2008 07:41 am ET | Updated May 25, 2011

PHILADELPHIA -- The Pennsylvania primary launched Hillary Clinton on a difficult, but feasible path to ultimately leading the nationwide popular vote in the Democratic presidential race.

In yesterday's Keystone State primary, she cut Barack Obama's national overall lead by some 200,000 votes. That still leaves him half-a-million votes ahead (not counting Florida or Michigan) -- a lead of about 1.6 percentage points.

The nationwide popular vote race is significant because it represents Clinton's only chance for a winning argument to Democratic superdelegates who will ultimately decide the outcome. Given the way Democrats proportionally (or is it DISproportionally?) award elected delegates (no winner take all), it appears all but impossible for Clinton to catch up in the pledged delegate category. Likewise, Obama cannot get to victory in this category, which is why the superdelegates rule.

With her 200,000-vote margin of victory in Pennsylvania, Clinton can edge ahead of Obama in popular vote by the end of the primary season in early June. To do so, she must hold his leads in North Carolina, Oregon, South Dakota and Montana to no more than 10 percentage points, beat him by at least two percentage points in Indiana and post big double-digit wins in West Virginia, Kentucky and Puerto Rico.

That is a tall order, but that's what it takes for Clinton to impress the remaining 250 undecided superdelegates. More on Craig Crawford's Trail Mix.

Now on Video Trail Mix: Craig covers the Clinton victory party in Philadelphia