I might have the opportunity to screen 1 or 2 movies at a get together soon. Crowd is generally chill people but not all comrades. past features (chosen by others) have included Shaun of the Dead, Rear Window and They Live, but I’m up for anything, I just want it to not be a complete downer, at least the first one, and ideally have communist themes or undertones.
Inglorious Basterds honestly is on the list as a fallback, always a crowdpleaser, but I’d go for something higher-brow if I could think of anything
Some that come to mind that might fit the request:
Shoplifters
Burning (edit: or maybe not since you said no downers. That narrows the field.)
District 9
Good Night and Good Luck (explicitly about red scare shit, but very normie-friendly + George Clooney)
Matewan (similar issues to above, not very subtle)
The Motorcycle Diaries (about Che of course but still just a beautiful film for anyone who isn’t already anticommunist)
The Wind that Shakes the Barley (Though that one is very heavy/downer, maybe could still work for the later showing)
But I also want to mention that it’s always a good idea to talk to libs (or just people who aren’t leftists) about the film afterward and emphasize the stuff that was actually leftist. I dont mean blatantly explain to them the left messaging in the film, but just casually mention a left-leaning theme or even relate a scene to something political irl "weird how much <x movie event> reminds me of <y current/historical event>. Because the sad reality is that most “apolotical” people and definitely libs will take the exact opposite message from what was intended, often relating the bad guys to communists (Star Wars’ Empire was the Soviet Union!) or misinterpreting something satrirically critical as being an endorsement (Starship Troopers shows us how important it is to have a strong military!) etc. To be effective with your film choice, you also have to goad them in the correct direction (leftwards) or it will go over their head or have the exact opposite effect.
Here’s an old comment from @dead@hexbear.net that I spotted saying the same sort of thing and also includes more suggestions: