Bernie? He's an Outsider who's not either Stupid or a Bigot. ( See Donald Trump

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AND he seems to realize that it's to his advantage while running for office to REMAIN an outsider, hence he's not taking money from the usual corruptive influences. Instead, he's getting media attention (and money) thru Grass Roots support, limited money from private donors.
He's also using Social Media feeds to gain support, as President Obama did while running for office (Go ActBlue!).
NO Corporate or Wall Street money like Hillary, NO Super PAC money like the Tea Publican GOP primary insiders.
Because of that, there's another VERY large difference between "The Donald" and Senator Sanders, one that should serve all of us once he's in office. This difference applies to Hillary Clinton, also.
Senator Sanders has ALWAYS been an outsider, and is actually running on that premise. In fact, he's been elected on that platform for his entire political career, and Big Money sources haven't ever purchase an election for him. Hence, he's not a Sock Puppet for any of those Special Interests.
In his case it's actually Integrity that defines him as an outsider, not politics as usual to support an election campaign.