JAKE TAPPER: Pennsylvania Democrats set to defect: “In a sign of just how divisive and ugly the Democratic fight has gotten, only 53% of Clinton voters say they’ll vote for Obama should he become the nominee. Nineteen percent say they’ll go for Sen. John McCain, R-Ariz., and 13% say they won’t vote. Sixty percent of Obama voters say they’ll go for Clinton should she win the nomination, with 20% opting for McCain, and three percent saying they won’t vote.” I blame racism.