Yes, although this phrasing seems to assume that there's a real negotiation during the campaign and that candidates are expected to make pledges with stick-to-em value.

Republicans spout extremism, pressuring Democrats to the right.

Asymmetrically, Democrats can't pressure Republicans to the left. Republicans will simply ignore whatever Democrats say, throw logic and empathy out the window, and say and do whatever they please: lies, extremism, BS that doesn't know whether it's true/false/reasonable/fringe. Republicans are merely performing for ratings, not negotiating in good faith or promising outcomes.

Harris may of course change her mind on any topic based on new information she receives, but she really oughtn't concede any point to the Republicans because the party isn't a real partner in governing; they're just a massive disinformation machine that operates on harassment. No leader or voter will reward her transactionally for anything she concedes to them.