It looks like others may be looking beyond this characterization, such as with this story about John Kerry from Mark Shields:
Let me tell you about a John Kerry much different from that glib stereotype. Seven years ago, Kerry personally recruited Brendan O'Donnell, then 19, to become an intern in his Senate office in Washington. Senate internships are coveted positions, often reserved for the children of well-connected or deep-pocketed campaign donors. Brendan O'Donnell's mother, Kathryn, was an honored elementary teacher and a widow. Her husband and Brendan's father, Kirk, was an enormously talented lawyer-politician had died unexpectedly the previous September. In the cold calculus of power, neither Brendan O'Donnell nor his family could do anything politically for John Kerry or anybody else.
What I forgot to mention is that Brendan is learning disabled. In 1999, he explained his condition this way in a statement John Kerry later quoted on the Senate floor: "I think there should be a different name for learning disabilities ... to me, it's not a disability -- it's just that I have something which causes a storm in my mind. When I look at something, I have to take my time and take it all in." But take it in he does, performing all his assigned tasks in the Senate office with enthusiasm and dispatch.