It's the name she chooses to use. Back before she had to run for office, everyone called her Rodham Clinton. She could have stayed Rodham when she married too. To call "Clinton" her husband's name is just as sexist. He's been married to her for more than half his life, and she has used the name Clinton for more than half of hers. She might not have been born with it (but then neither was he), but she has made it her own.

And the left's affection for Obama, or detestation of any number of leading Republicans was? The hatred for Nixon was far closer to pathological, and don't go blaming Watergate for that - Watergate happened because of that hatred, not the other way around. Nixon's ethical misconduct as president was a fraction of what was ignored under Johnson & Roosevelt. Much of the complaints about Nixon, such as his enemies list, are bullshit. Bush was hanged in effigy and a book and movie were made fantasizing about his assassination. What equivalent has been done to (either) Clinton?
I would assume a more objective person would categorize those as "reasons with which you happen to agree" as opposed to other reasons which are "pathological".

That's the way its been for decades. The myth is that there is a small swing group that both sides try to appeal to, but a recent opinion piece I saw somewhere made the much more plausible claim that there is no real undecided group, that both sides campaign to rally the base and get a turnout in their favor. I would hazard that the leftwing media has been promulgating the swing vote theory hoping to induce Republicans to try leaning left to garner these alleged centrists, when the reality is that conservatism sells and has been responsible for nearly every GOP presidential win in the last century or so. Dole & McCain & Wilkie & Dewey & Bush I failed, with the latter winning his sole election as the perceived successor to Reagan. Bush 2 ran as a more conservative candidate than he actually served. Once safely into his second term and he began trying to appoint women with no credentials to the Supreme Court and offering amnesty to illegal immigrants, he lost the good will from running as the anti-Clinton and then based on his supposedly strong post 9-11 performance.

I think Trump's success will depend on being able to draw out more people who ordinarily wouldn't give a crap, in addition to the 'anyone but Clinton' vote, than he will lose by not being allowed to appear sufficiently "presidential".