I think he truly does have a good heart, and I would absolutely vote for him over anyone else.

There was recently a story running around that he used some of his campaign funds to fund his step son through the Sanders Foundation, but it's hard to find non-right wing sources on it, besides maybe this one from the Atlantic. It's not a huge amount of money in the grand theme of things, but it's potentially a small tarnish on his otherwise fairly spotless record.