W. C. Prime organized a miscellany of the late George B. McClellan's writings for publication under the title McClellan's Own Story, a work that had him meeting and corresponding with the illustrator for that project, the famous Alfred Waud.
In a letter to Prime dated June 16th, 1886, Waud reported on the status of some drawings and then launched into an account of a subject "we spoke of." He adds, "Genl. McMahon says he had some evidence bearing on the same subject at your service."
Prime did not use the anecdote Waud provided; neither did Sears in his McClellan biography. Waud's letter appears in the McClellan Papers, Library of Congress, where it has languished in obscurity until Russel Beatie analyzed it in Volume 1 of Army of the Potomac. Here is the memo part of it, in his own spelling and punctuation.
One evening in the winter of 1861 being in the rooms of the New York Tribune at Washington in company with E. House, one of the correspondents, I found a number of members of Congress present. I did not know all of them, but I remember seeing Washburn, Wade, Wilson, Cochrane and others, in all twelve or fifteen.
In the course of the conversation it was plainly stated that it was not in the good of the interest of good statesmanship that the rebellion should be suppressed at an early date. It was agreed that the true policy of the country, and of the party, was to prolong the struggle, till the people of the North were educated, or exasperated into the point of demanding emancipation as one of the necessary results, and till the Southern power and influence should be so shattered, that the republican party would have no difficulty in retaining control of the government for many years.
It was therefore plainly necessary that no effort should be spared to get rid of McClellan, whose only idea was to make speedy end to the war, in which case he would be naturally, as a successful general, the choice of the people for president, but in no way an exponent of the dominant party. Being too popular with the citizens and the army to openly oppose, he must be assailed in other ways.
The meeting then broke up.