@JPB,
For quite a while, I've been saying (and more so, believing) that the US is headed for a political sea change due to the reasons you stated.
I think you're correct in your estimations that the one thing that the Trump and Sanders groups have in common is their utter contempt for corrupt politics as usual. These crowds are enormous and excited...about POLITICIANS. I've spoken to a multitude of people, who like me, have donated for the first time to a political campaign - and are HAPPY to do it. The dynasty candidates, Clinton and Bush, couldn't be more apt metaphors for this drama.
I wonder if people really think about how the impossibly wealthy, big name recognition candidate who has Wall Street in her back pocket and was leading as though she were the only one in the field is about to lose to an elderly, grumpy, agnostic, Socialist Jew, who refuses PAC money.
Think about it.
Something's very different.
I hope we see at least one party split. It looks like it'll be the Dems, and it may cause a loss this time. There is a deep division within the party; old party loyalists are refusing to donate to the DNC and calling for the dismissal of DWS. I've witnessed this division deepen over the months since Bernie's entrance into the campaign.
I don't think anything is going to be the same.