A loneliness about him

I think Lance Mannion's article is probably quite perceptive because he brings his knowledge of performance and drama to this analysis:

What some have called his cool, others have called reserve, and others have resented as aloofness, appears to me to be a deliberate, disciplined, stepping back. He's watching himself with a deeply critical and skeptical eye, ready to come down hard on the first sign of an emotion or egoistic urge getting out of hand . .
Good performers---and a politician on the stump is a performer---are often their own toughest audience, particularly the ones who aren't naturals. Some performers are able to watch themselves with a sense of humor, others with an ironical detachment. Obama seems to be watching himself with an open grade book in his hand.
And there's a loneliness about him. . .
with Barack Obama we have a President-elect who is a reluctant public figure. He strikes me as a brilliant, active, but scholarly man, introspective, even introverted, who's been granted gifts for public speaking, moral persuasion, and leadership that he is temperamentally not inclined to enjoy . . . I think Obama became a politician because he felt it was his responsibility, not because he thought it would be fun.

And he goes one to discuss why Joe Biden, who does think politics are fun, is Obama's perfect vice-president:

Biden's the guy you can see reminding an annoyed and exasperated President Obama to smile and nod while listening to a blowhard and a boob waste his time by smiling and nodding himself. Biden's the sort you can see walking you to the door after you've just been dressed down and having you convinced by the time he's helped you on with your coat that you've been given a medal and a two-week vacation . . .
Biden, I think, is the perfect complement to a basically shy and skeptical man interested more in policy than in other politicians, drawn more to individuals than to crowds, more at home in private than at ease in public.

I think this may be why it took Hillary supporters a little while to warm up to Obama, because he didn't have that spontaneous, warm, gregarious manner.
But once you get past that difference, then his commitment to leadership and his simple basic decency simply shines.