Tom Oliphant has known John Kerry for over 30 years.  Oliphant profiles "The Kerry I Know" in this American Prospect article. 

According to Oliphant:

"John Kerry is a good, tough man. He is curious, grounded after a public and personal life that has not always been pleasant, a fan of ideas whose practical side has usually kept him from policy wonkery, a natural progressive with the added fixation on what works that made FDR and JFK so interesting. I know it is chic to be disdainful, but the modern Democratic neurosis gets in the way of a solid case for affection. Without embarrassment, and after a very long journey, I really like this guy. As one of his top campaign officials, himself a convert since the primaries ended, told me recently, this is pure Merle Haggard. It’s not love, but it’s not bad."