My gut feeling is that it all won't matter. I think the majority will vote for her no matter what. And the Republicans are at a huge disadvantage anyway - the media is biased and cares far more about Bush's fumble of a single question that he obviously misunderstood, and Christie's "bridge gate", Perry's gaffe in the 2012 primaries, etc, etc. I think the fix is in. But I hope I'm wrong. http://freebeacon.com/culture/by-george-abcs-clinton-defender-in-chief/
This is just a personal version of wikileaks. It all depends on whether or not she is able to put a positive spin on it. Reagan and Nixon basically did the same thing, the only difference is Reagan being an actor managed to put a positive spin on things. Wikileaks is far worse then anything Clinton has thrown out, and for the most part the public has ignored it. The general public now days seems to be pretty appathetic about things.
Nixon was only guilty of getting caught and being paranoid. Nowadays, you can bet the President has a staff member just for hiding his tapes. I sincerely doubt that the she-Clinton wasn't under constant scrutiny from the Secret Service. What it comes down to is whether someone can hold her to the grindstone on it. She can either spin it in her favor or be attacked over it. If she's attacked over it, it would be extremely easy to use the Secret Service to say 'Well, it was National Security related. We had to clean it out,' as a get-out-of-jail-free card.
