[az_gila]

Third parties can, rarely, be successful in a parliamentary system.
We do not have a parliamentary system.

The way parties change in the USA is: they lose multiple elections until a new faction within the party gets the reins.

No third party has ever become the dominant party in US history, due to the structure of our Congress.

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In the UK Parliament the UKIP Party is actually a fourth party after Labour, Conservative and Liberal Democrats...

[wideawake]

Good point. See post 20 - I corrected myself.