The conventional wisdom going into yesterday's primary in Pennsylvania was that Hillary Clinton needed a substantial win over Barack Obama to stay in the race. Her 10-point win seems to have qualified as substantial.
What's nice about this is that the internecine warfare between Obama Democrats and Clinton Democrats will continue. With Indiana's and North Carolina's primary two weeks out, look for the political equivalent of WMDs and battlefield atrocities to be committed by both sides. Obama has a 13-point lead in the polls in NC, but just a 5-point lead in Indiana. But keep in mind that those numbers are pre-Pennsylvania and are bound to shift in Clinton's favor.
Mutually Assured Destruction!