A good liar always sells his deceptions when folks are distracted by other activities, characteristics or mannerisms. . A smile, exuberance, extreme confidence, all work to draw attention away from the deception. Women and effeminate men tend to be most vulnerable since they think with their emotional parts rather than using reason and empirical tests to disseminate.
And that’s why Obama gets by. He is nothing if not polite. He may be the most polite candidate amongst this recent group of primary candidates.
As long as the MSM & his machine (and now Biden) continue to insulate him from direct and real threats on his character & ideology, he will use his polite demeanor (and, as always, the race card) to schmooze his way to the White House.