IMHO, it will take a major uprising against existing politicians to bring a third party into strength to start winning things....but that day may come.
Keep your Glock oiled and ready
It's highly unlikely. The Republicrats learned their lesson after Ross Perot, and clamped-down on third parties. Top that with Campaign Finance Reform to make it difficult for smaller parties to raise money and there's virtually no chance except in smaller state races. Even then, the Republicrats have that "straight ticket" check box on many state ballots to make it easier to vote for just them, excluding other parties.
The only positive change I've seen over the last several years is the relaxation of state election laws due to challenges from other parties. It's still hard for other parties to get on the ballot (while the Republicrats get on automatically), but it's not quite as onerous in many places now.
Republicans and Democrats fight with each other all the time, but they will always band together to defend their duopoly.
I think there will be a third party, a strong one, sooner rather than later. It's going to be a mix of dissed dems (those that Nancy will throw under the bus), conservatives and a mix of a few other parties.
Maybe I'm wrong, I'm so befuddled today after last night...
Dream on.