Interesting choice. Actually makes my point.

And Bernie Sanders. Twice. And Elizabeth Warren. And plenty of other progressives/socialists that have lost ordinary, run-of-the-mill contested primaries and general elections. Nor would you expect that a genuine class warrior wouldn't have massive spending against them, either.

When you say, "[w]henever voters are given a chance to elect genuine class warriors, they get excited," that's true - but only for some voters. Likely the voters whose positions agree with your own, and probably the voters most visible to you. But not all voters. There are plenty of votes who don't get excited about genuine class warriors - and other voters who are 'excited' with a desire to defeat those candidates.

Running "genuine class warriors" only increases your chances of recapturing the working class voters that have left the Democratic Party if those voters are actually looking for genuine class warriors. If what they're looking for is candidates that will be conservative on social and cultural issues, though, picking those folks is not going to do much to bring those working class voters back, and indeed might make things worse.