Part of the charisma may stem from a sentimental transformation of the victim --- and it is usually a victim --- into a figure that would have been unrecognizable to his/her contemporaries . . . .
I agree, but I would argue this is the charisma of the memory, not of the person. In fact, I think it is possible to view charisma as something that flows not downward from the person credited with it, but as something that flows upward from the audience who conjures it to fill a need
they perceive.
Back to charisma; at least part of it is charm, which Hitler certainly did not have (most people in the inner circle were bored by him in social situations . . . .).
Hitler is an interesting case. While he could certainly be a boor to some in close quarters, one has to remember that some of his entourage were willing to kill themselves
and their children in service of the dream with which he inspired them. And there are simply too many contemporary reports of the mesmerizing effect he could have on crowds to dismiss him as uncharismatic. Given what we now know of his true personality, it would seem an illustration of the point that charisma is actually a phatasm of the viewer rather than a trait of the viewed.
Alexandra is almost the inverse case to Hitler. Known by her intimates as kind, thoughtful, in possession of a sense of humor, she was vilified by the public as a nagging, interfering harpy who kept doubtful company.
In fact, I think Max Weber's seminal definition suggests the same view: "Charisma...a certain quality of an individual personality by virtue of which he is set apart from ordinary men and treated as endowed with supernatural, superhuman, or at least specifically exceptional powers or qualities. These are such as are not accessible to the ordinary person, but are regarded as of divine origin or as exemplary, and on the basis of them the individual concerned is treated as a leader."
As a person who does not believe in supernatural or superhuman powers, or even the granting by God of special powers to specific individuals, I find it much more reasonable to locate charisma in the audience's perception than in the actor's gifts.
People who show up on one list or another of charismatic leaders (and they vary widely) seem disproportionately to be people who met a violent or ignominious end: Julius Caesar, Richard III, Napoleon, Hitler, Nicholas II, Lincoln, Eva Peron, Kennedy, Martin Luther King, Jim Jones, David Koresh, Charles Manson . . . Jesus. As Louis Charles noted, becoming a victim is a giant step up the ladder to charismatic status.