The thing is, I don't think anyone on the "lefter" end of the spectrum is saying we need to worry about the "white working class". The only place I really hear that coming from is the media or people toward the center who want us to be more socially conservative or reserved on identity issues.
I think Bernie in particular (and for the record I was not a Bernie supporter) was and is saying that we need to speak to the working class in general which encompasses all races, genders, and groups, and whose impact affects everyone. That's what the article is saying but it also seems to be implying that the more progressive end of the spectrum is calling for an appeal to the "white working class" when in reality all anyone is saying is that we need to better sell our economic policies, assuming that our candidates actually agree with them.
The issue I've had with the party in general the past decade or so is too many candidates willing to just say "Well yeah, I support that it's in the platform...." as far as economic issues but without actually selling those policies. Without pointing to the mountains of data and numbers that show that progressive policies work. I feel that's one thing that Clinton did wrong. I think it's really the one big thing Obama did wrong. I know that there's a lot of stuff that is too deep to go into without people's eyes glazing over. But the thing is.....it's not my job to come up with those things. The problem I have and that many have is that we have tons, TONS of highly paid people who are supposed to be experts on this stuff who seem to fail upward within the party and those are the ones we need to get rid of and start hiring people who can sell this stuff. I don't even expect candidates to come up with this on their own. But I expect them to hire and listen to the right people that have proven track records of good communication and not just loyalists who tell them what they want to hear.
Also, that article had waaaay too many typos and grammatical errors, but that's another issue entirely. 
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