He provides some clues to the source:
The name of the source is one that you would surely recognize, since he commands respect throughout the mainstream media, not just in blog-world. He is a famous investigator. For that reason -- and for another reason which will soon become clear to you -- I will here call him "Sherlock Holmes."
(Consider that a clue.)
I greatly admire Sherlock's previous work. Most of it, at least. You probably do as well. However, he has been fooled in the past. His most infamous slip-up concerned a story about a person I will here call MM. Fake documents were involved in that instance.
(Consider that another clue.)
My guess on the source is that it is Seymour Hersh (Sherlock Holmes=SH=Seymour Hersh, Marilyn Monroe=MM):
Hersh thought he had happened upon a previously buried treasure-trove of documents proving all kinds of previously unsubstantiated allegations. Newsweek reported that a series of signed agreements dated between March 1960 and Jan. 1962 allegedly proved that Kennedy paid Marilyn Monroe more than $1 million for her silence -- not just about her long-rumored sexual affair with John Kennedy, but about JFK's purported relationship with mobster Sam Giancana and other "underworld figures."
If it is Hersh, I personally do not consider him that reliable.
Update: As important as it I think it is that Republicans win this election, I do not want to win it because Michelle Obama turns out to be a "racist POS". I want to win this election because the American people come to realize that Republican ideas are much better for the future of America.