Allow me to put forward a hypothesis that will be very controversial: Sanders supporters were, by and large, held together by his promise of free college education.
I suggest this because, despite being billed as a populist, he was something of a niche candidate. Educated millennials made up the bulk of his support. (You get zero points for showing he had support elsewhere; there are approximately a zillion articles from the primaries about the correlation between age and support for Sanders.) It is hard to point at too many specific programs Sanders supported—one of the reasons this blog criticized him was that he was consistently vague. Yeah, I want “less income inequality”, but Sanders stump speeches offered few details on how we were going to get that. One of his few concrete ideas was a plan to tackle student loan debt.
Clinton treated it as a non-issue.
Sure, she said a few applause lines when Sanders put the pressure on her in the primary…but they were unconvincing. And she dropped talk of it once she was campaigning for the general. Part of the reason was that Sanders’ plan was wishful thinking covered with some vague gesturing; his preferred examples in the Germanic world send far fewer people to college and the programs are subsidies for the upper-middle class. He tended to dodge these questions by pointing out that Congress could raise taxes enough to cover everyone, but without really grappling with the underlying dynamics*. Clinton correctly avoided promising something that would be difficult and costly to deliver until she had to. But part of the problem was that the Clinton campaign underestimated how much that issue was contributing to Sanders’ appeal and what that would mean in November. For that matter, I did too.
I would caution against reasoning from the case I’ve laid out here that Sanders would have won if the Democrats had just run him. Clinton got more votes in the primary, and those were her most reliable supporters in the general. Sanders could have brought in the millennials, but its not clear that older democrats would not have just sat this one out instead. It’s possible Sanders would have won, but it is by far the less obvious conclusion.
The easier lesson is forward looking. Whoever runs in 2020—and for that matter, 2018—must have a real plan to address student debt. There is going to be a very delicate balance to strike. Older democrats are correct that the flashiest proposals are unworkable and must be made unfair to work. Younger democrats are right that the status quo is untenable.
Getting both to the polls is the only option for democrats.
*Paying for all tuition would require increasing the federal budget by about 9%. This sounds modest, but in absolute terms that would be about 353 billion dollars a year. Making it free would likely increase the number of applicants, meaning some kind of rationing would be necessary even if we held numbers at current levels; Universities would have every incentive to enroll as many people as possible to get more Federal funds. That’s also a noticeable tax hike that would affect whatever market Sanders chose; he chose the famously elastic investment market but assumed no elasticity. Sanders tended to treat these points like distractions rather than very real issues that impacted how fair workable his program was.