...And IMHO she's a total idiot that shouldn't be in office. ...
It's easy to say such things. I would always suggest giving people the benefit of the doubt.
In an egalitarian society, the chances would probably be roughly 50/50 that someone elected to public office would have an IQ of less than 100, or more than 100.
More doesn't necessarily mean better. Arguably many people with an apparently low IQ and holding public office would seem to have been able to demonstrate that they could function very responsibly in their roles in society and not seem to behave or think stupidly. However, many with an apparently high IQ would seem to have been able to demonstrate that they can get away with being totally misguided and acting like complete idiots - a classic example possibly being the UK PM Chamberlain in wanting to appease Hitler, but then he died of cancer six months after leaving the premiership, and in my experience people with cancer can start to exhibit muddled thinking some considerable time before their cancer is diagnosed. In other words, people's ability to think straight could be affected by their state of health, just as (say) by their level of alcohol consumption.
From experience, whenever I have seen people behave out of character or irrationally, there has generally been something apparently wrong with them, physically or psychologically. So Senator Diane Feinstein could, for example, actually be ill and unable to reason properly or even reflect on her own past actions sufficiently objectively to be able to be honest and open about this - in which event, she could not be relied upon to be honest/reliable. But this would not necessarily be because she is a bad or stupid person, but possibly because she is or has been unwell.
The other things that give rise to apparent irrationality could typically include, for example, being trapped in a belief in a particular religio-political ideology, or committed to some criminal intent, but I would presume neither of these would apply in Feinstein's case.
Of course, if, despite the above, it turns out that she has in fact always been just a complete idiot, then one would need to examine how her appointment to public office came about in the first place. "You get the government you vote for."
In any event, God spare us from a technocracy or elitist ideology ruling our lives, or an idiocracy...