I recall her having HUGE favorability ratings now... I like her, and so do most Americans.
Latest PPP poll on HRC:
https://uselectionatlas.org/FORUM/index.php?topic=169084.msg3618192#msg3618192
favorable: 49%
unfavorable 42%
So net of +7%. Down from +15% from just last month. IMHO, all the talk of her running in 2016 that's circulated in the media during her retirement as SoS has already "re-partisanized" her a bit.
I wouldn't be surprised if the Benghazi hearings had a part in it, she got really fired up against the Republicans. Having Lindsey Graham saying "she got away with murder" and Rand Paul"saying she should be fired is really strong rhetoric that probably resonates with Republicans who might have been approving of her hob as SoS.