We can't afford a split vote as elections are close. If Bernie Sanders runs as an Independent candidate, he will do just that.
Bernie would also get the support of the Democrats if he won the primary, which I think he has a good chance of doing and would receive a lot more funding, something he needs if he really wants to win.
In summary, we will lose if Bernie Sanders and the Democratic frontrunner each get 30 percent of the vote and the Republican's get a minority of 40 percent of the vote. Let's ask Bernie to do the smart thing that will ensure him the best chance of winning the election against the Koch Brothers. Let's ask him to run as a Democrat. Can you imagine what damage a Republican president would do again? Never forget Cheney and Bush.