[H]ave the attacks on O'Donnell been "sexist and misogynistic"? Sure, they have been glib and mocking — par for the course when there's so much video evidence of her insouciant wingnuttery. And they have involved sex, but only because that was O'Donnell's topic of choice until she discovered a vague and sudden passion for tax cuts.
It's fair to say that within a patriarchal society, any woman that is being scrutinized and attacked by mainstream opinion is going to encounter the same kind of hostility that women with much lower profiles experience all the time, solely on the basis that they are women.
Because a solidarity with women finds its roots in the recognition that patriarchy works actively to harm and subjugate women, feminists should work actively in anticipating that this will be as much the case with specific, well-known women as we already understand it to be the case with every woman -- if not more.
Defending someone on the basis that they are a victim of patriarchy is no different than advocating for someone on the basis that they are working class: it is a position that is maintained on specific grounds; namely, that people who are being victimized, for whatever reason, deserve support.
For example, there are plenty of working class people who are racist, misogynistic, or homophobic who at the same time are victims of globalized capital (and by "working class" I do not merely mean "blue collar"; I mean all workers). Wobblies understand that all workers deserve solidarity in their struggle against employers and other bosses. They should also know that the best way to confront racism, sexism, and homophobia (among other violences) is by organizing along these lines: to extend solidarity to the victimized, and to confront the victimizers in all relations.
Practicing solidarity with women is no different. Hillary Clinton and Sarah Palin deserve to be confronted for the various ways they advance authority by illegitimate means. But they have also been attacked by illegitimate means, on the grounds that they are women. And while I haven't followed the O'Donnell case closely, unless we convince ourselves that mainstream liberal culture is not patriarchal, we can expect that the same anti-woman sentiments will find their expression in the course of a heated Senate campaign.
The point is not that Clinton or Palin or O'Donnell deserve special attention in this regard, but that nobody ever deserves to be attacked on the basis of any illegitimate criteria. Wobblies know very well: An injury to one is an injury to all.