In the conduct and management of the affairs and procedures of the Democratic National Committee, particularly as they apply to the preparation and conduct of the Presidential nomination process, the Chairperson shall exercise impartiality and evenhandedness as between the Presidential candidates and campaigns. The Chairperson shall be responsible for ensuring that the national officers and staff of the Democratic National Committee maintain impartiality and evenhandedness during the Democratic Party Presidential nominating process.
Again, I prefer Sanders, or even Johnson or Stein over Clinton; but with Trump on the other ticket this election is far too serious to let Russian fuck around with the other main side. We need to fall in line and support Clinton. Pulling the not-an-idiot vote three more ways between Sanders stay-at-homes, Johnson / Stein protest votes is going to lead to a disaster.
Parties choose their candidates. While it is democratic in the sense that people cast ballots; the process was never guaranteed to be a level playing field. Sanders was an outsider from the democratic party. The party has rules and systems to keep people like Sanders out. That is what super delegates are for. You and I may both have preferred Sanders, but we don't have a right to the DNC's private email.
As for the polls, in Canada we do a simple pencil and paper system that works extremely well. You might be able to get an extra vote or two here or there, but the process is essentially unbreakable.