Sanders will, of course, throw his full support behind Biden as he did with Hillary Clinton. The two men are friends and like and respect one another. So, I don't see any issue with that. The voters...well...I don't know what they will do. Also, based on what happened recently in Wisconsin and our Supreme Court ruling in favor of Republican voter suppression would indicate we are going to have plenty to overcome to oust Trump. 

I looked up Rogan and his Biden comments. It seems his issue with Biden is he does not think Biden is capable of serving 4 years as president and that he feels he has already slipped too much from a mental standpoint to be a viable candidate. I certainly think that Biden seems to have some issues but I mean you could run a set of steak knives against Trump and it would be better option.