See e.g. the conservative pundit William F. Buckley Jr, who spoke with a really classic example of this accent (and was alive much more recently than most people who spoke like this):
He had an interesting history. I guess English wasn't his first language. And he spent some time going to school in England in his early teens. I'd guess he came by that fascinating accent honestly. Not quite British, not quite American. And he spoke with a melody, very flowing from one word into the next. It does make him sound a bit aristocratic.
https://www.youtube.com/watch?v=p0d8mzdr4jE
It's such a weird mix of British and American locution. I've never heard anyone speak like this in real life, and they did I would look at them funny.