From Rick Moran:

With the press eager to jump on every sign of disunity, with a former candidate whose supporters think she deserves her moment in the sun, with a former president probably secretly wishing that he loses in November, and with his poll numbers stagnating or dropping, Barack Obama faces the greatest challenge to his leadership of the party and his chances for victory in November in Denver three weeks from now.

How he handles these problems will no doubt affect the decision of the American people when they go to the polls in November.