"Politically, he correctly believes that he would be called out as a hypocrite if he practiced the conventional art of attack politics after preaching against it.

And, to view his motives in the best light — a benefit of the doubt extended by his own team — he believes this campaign would also undermine his governing strategy if elected. He has told associates it would be impossible to win support for a progressive agenda unless he assumes the presidency as a uniting figure who can transcend the personality-obsessed brand of combat that has dominated Washington for the past generation. "