Lately I've been watching a lot of C-Span. Perhaps it's an indication of how exciting I am, but I found a rather interesting series they've been working on recently about US Presidential Contenders that "lost, but changed history". So if you've ever had a soft spot for one of these guys or never heard of them, I'd recommend to give their video a viewing.
C-span has a lot of interesting material. I was aware of the Book TV stuff and usually try to see the show about various new books. Thanks for posting about this series since it seems to be interesting and well done. There are only 2 contenders (of the ones you listed) that are still alive and McGovern was just recently released from the hospital.