I think he's the only candidate who can beat Clinton.
I'd have to disagree. I would say that just about anyone sane could beat Hillary in the upcoming Democratic primary. She has what I like to call "Howard Dean" syndrom. Yes she is polling high because she is the only candidate that Democrats believe they have at the moment. The second someone else enters the race (by someone, I mean someone serious, not Mike Gravel) she'll fall off the map and finish third in the primaries.
No, not quite.
Hillary has more name recognition than Dean did (I'm talking about your average voter, not a few beltway activists) more money than Dean, and the best political machine (and genius, in the person of Bill Clinton) that can be found.
She could be defeated by a united effort by party moderates to unite around one candidate during the early primaries (Warner, Bayh, Richardson..whoever) but she isn't going to simply die away, that's assured.
Most of what you say is true, but you are not taking into account that people don't like Hillary half as much as they liked Dean. At the time "Crazy Howard" was a very popular figure within the leftist realm of the party. Not one wing of the Democratic party is really enthusiastic about her where as at least Dean had the left.
I think you bring up some excellent points. Clinton really only has her name going for her, I haven't found anyone yet who is extremely enthusiastic for her. I think her support is mostly because she's so well-known, so when people are asked they default to the name they know.
She is certainly far from the darling of the left that she is portrayed as by the right.