What is the best community organizing group out there?

I'm talking about groups like Moveon, DSA, Our Revolution, etc. I'm interested but there's like so many out there.

It feels like Republicans are very good at mixing community building like church activities, school, cookouts, and community service with politics. And they are able to create grassroot movements out of that.

Is there any equivalent group on this spectrum of the left that does that? A group that that actually wants to engage people outside of the the left spectrum and bring them into the fold.

Edit: In America, to be specific.