“....Much like the ducks know when it is time to fly north or to return south.....”
It would have to be due to a “follow the herd” reaction. There has never been in her any evidence of independent rational thought. Of course there is always a first time. She might it liberating!
Liberals don't think, they use feelings and intuition. And that is what may be happening here. As you say, they are basically herd animals and if a few start moving in one direction the rest may follow.