A question regarding the 1964 presidential election

I don’t know anything about the ins and outs of the 1964 election beyond the fact that Goldwater lost in an enormous landslide, and that the Johnson campaign ran the infamous Daisy ad (one time only IIRC) to drive home Goldwater’s purported taste for nuclear war and/or his mental instability.

So a question or series of related questions for the more knowledgeable: did Goldwater’s campaign cause any sort of tension or rupture among Republican elites? Did any prominent GOP figures refuse to endorse him, or try to pull a Ryan/Ayotte by splitting the baby? Was there anxiety in the GOP at the time that Goldwater’s views on civil rights were going to do long term harm to the party? What sorts of parallels, if any, can be drawn with the current GOP chaos?