It's even possible Favreau is specifically saying the Democrats DIDN'T go after the electoral majority because they were influenced unduly by special interests to go after the centrists when they could have been going after the people who didn't vote at all (for whatever reason)

That's how I first read it. Idk though, I'm not exactly sure what Favreau's trying to say here

Edit: I reread the tweet a couple times and I think that your interpretation is correct. He specifically calls out corporations and donors as the groups that Dems should resist, and calls dems to focus on the electoral majority (like you said, potential voters) and if that's what he meant then I agree with him.