There’s a bunch of survey based research showing the left generally moving much more than the right.

I think there’s a reasonable question about whether these are real beliefs or just uniformity in partisan talking points.

Ah, haven't seen those maps.  That's an interesting data point that I didn't know, but it "feels" right based on observation.

SimpleStacker

What about those ideology maps that show Democrats (or liberals, I forget the framing) being more tightly clustered than Republicans?