Halperin lists "what John McCain underestimates" about Barack Obama. Number 13 stands out:

How powerful debates might be when the allegedly inexperienced Obama of allegedly questionable judgment goes toe-to-toe with McCain, even on national security, and is therefore deemed of sufficient strength and stature to be president by many.

That's the trouble with basing a campaign on the other guy's unfitness for office. What if he proves you wrong on the campaign trail?

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