The republican party is an excellent recent example for this actually. The teabaggers rebellion didn't run third party candidates, they ran in party primaries and started knocking out incumbents. The remainder of the party saw this in action and moved fairly quickly to align with the insurgent faction out of simple self-interest. The result was that the party shifted rather significantly to the right to accommodate them which meant that they ended up getting much of what they wanted.
The grassroots, "teabaggers", and Ron Paul libertarians, did not get what they wanted. They were exiled from the party. The party rules were changed so that any sort of grassroots rebellion could be extinguished.
I understand the theory you're suggesting. It isn't working though. We aren't getting the liberty, peace, and prosperity we deserve. We're getting more of the same.
What we need to do is to choke that stubborn senile elephant, and replace it with what it use to stand for, libertarianism.
As far as the Democrats are concerned, well... keep it classy.