The main factor that has kept Trump’s approval rating low has been the constant drum beat of negative stories from the press. As you said, MDMikeB, most citizens don’t read much beyond the headlines and are, unfortunately, low information voters. All they hear are “Trump is a racist,” “Trump colluded with Russia,” and “Trump is mentally unhinged.” That leaves them with a negative impression.
Good news about the economy and dumb statements from “the squad” have helped Trump. Mueller’s poor showing at the Congressional hearings exposed the Democratic weakness on that issue, but the Nadler, Schiff and the news media are now doing all they can to cover that up and keep the false storing going. Whether or not the people see through that remains to be seen.
If you have followed the stories at all, you would know that the motives behind the Russia investigation have been to prevent Trump from doing is job as president. There is nothing to support what Nadler and company are saying, but they think if they keep saying it over and over, it will be accepted as gospel.
I think that the constant drumbeat of negativity from the news media is finally dragging them down. They have reported so much negative news about Trump that they have ruined their own credibility. It amazes me that they can’t see that. All they have done is respond with advertising slogans like, “CBS is good news.” That shouldn’t cut it in my opinion. So far as I’m concerned, I don’t trust what they report any more, not even medical news, unless it collaborated elsewhere. Even the medical stories are colored by “hip” liberal life styles, like veganism and climate change, which is always lurking behind their reporting motives.