Harry,
Bernie does have a plan to pay for "Medicare for All".  It will save middle class families money over what they're now paying and give them better results and choices.  
Already, the bandwagon for it has started rolling.  Trumpcare is making one last "death rattle" with Republican Speaker of the House and Republican Senate Majority leader Mitch McConnell.  As soon as the public learns of its details, it will be DOA again.