The essential fact of the current primary season is that Hillary Clinton has this apparent trump card when her rivals try to attack her from the left: Republicans really, really, really hate her. The debate opened with an invitation for Barack Obama to slam Clinton, he attacked, and then she rebutted: "Well, I don't think the Republicans got the message that I'm voting and sounding like them. If you watched their debate last week, I seemed to be the topic of great conversation and consternation, and that's for a reason, because I have stood against George Bush and his failed policies." Later in the debate she explained "I think that, you know, the Republicans and their constant obsession with me demonstrates clearly that they obviously think that I am communicating effectively about what I will do as president."
Barack Obama countered with what I think is the first effort I've seen to seize this bull by the horns:
Part of the reason that Republicans, I think, are obsessed with you, Hillary, is because that's a fight they're very comfortable having. It is the fight that we've been through since the '90s. And part of the job of the next president is to break the gridlock and to get Democrats and independents and Republicans to start working together to solve these big problems, like health care or climate change or energy.
There's something to that argument, but there are obviously limits to its cogency. Like Sally Quinn's loathing of Bill Clinton, there's just an irreducible core of irrationality to anti-Hillary sentiment. Part of it, obviously, is misogyny and the rest is just that same core that she shares with her husband and that prevents either of them from being perceived as the savvy (in both political and policy terms) moderates that they are. Obviously, that "Clinton Rules" treatment has been a problem for her at various points and doubtless will be again, but in the present context it's a big asset for her. John Edwards, though perhaps overstating a bit, is basically right to say that a return to Clintonism wouldn't constitution a fundamental change in American political economy and Obama's right to point out that Clinton seems to disagree with Bush's foreign policy more in terms of tactics than strategy. But as long as the entire conservative movement is deeply invested in the idea that she's a hard-core Communist, it's very hard to persuade people that these things are true.