Harris (along with Pelosi, Schumer and the radical part of the Democratic party) may well be the salvation rather than bogeyman. For whatever you may think of Muller’s investigation, no charges have been made which tie in any way to the collusion narrative; he has only charged people with the crime of lying to the FBI, tax fraud, or other crimes committed well before the election.
And the House Democrats have openly said they intend to pursue investigations which could lead to impeachment proceedings against Trump and Kavanaugh.
What many of the Democrats seem to be unable to grasp is that they are playing to their constituency, and are running a serious risk of alienating not only Republicans, but also Independents and the conservative end of their party. The phrase “Give them enough rope and they will eventually hang themselves” is at play, and history, while not exactly repeating itself, does rhyme - the Republicans shot themselves in the foot going after Bill Clinton.
Nancy already has Democrats saying “get over it and negotiate; give them the wall”, and are starting to do so publicly. Nancy telling Trump he will not be invited to appear before Congress for the State of the Union may not go over well with anyone except die-hard “impeach him” fans.
Harris’ performance, along with Hirono are not going to go away, particularly if Ruth decides to step down. Whether Amy Coney Barrett is proposed (which I somewhat doubt) or someone else, many of the judges proposed for seats on the Federal Bench have been women and men of faith, and the grilling has not been any less appalling for the blatant religious test. Amy would bring something close to a nuclear meltdown.
Kamala has a history both as a prosecuting attorney and as the attorney general which doesn’t do her any favors. As she is publicly running against Trump, she will be in the news at least weekly, unless and until someone in the party moves seriously ahead of her, or she simply does not chart well at all with the non-announced runners. The circus is just getting started.