I also suggest this. Even without documents...this rumor alone on the MSM or even talk radio will do damage. Just for the fact that it is highly plausible, and he won't release his military records.
Just last night I was telling my sons that a primary difference between liberals and conservatives is this: To many liberals, if not most, good is defined by the desired outcome and integrity and the truth are not necessary to promote good. To many conservatives, if not most, it cannot be good unless it is supportable by (way of) integrity and truth. (Romans 8:28 not withstanding)
I'm sure the minions over at CBS were convinced that the Air guard memo and missing explosives stories were highly plausible too...