I suspect he hooked up with whatever party was serving drinks.
He didn't drink. I suspect he was a Democrat, but certainly no wild-eyed commie liberal. Like Frank, I bet he was a Reagan supporter.
just a quick FYI- Dino's drunken routine was an act. He rarely if ever drank socially and was a devoted family man. As for Sinatra-he was a close friend of the Reagans and a staunch republican later in life. That is a great picture. My favorite president and three of my favorite entertainers.