“the “tea party” didn’t even fight Romney.”
They wasted their energy trying to sink every conservative in the primary over petty reasons, and that allowed Romney to walk in.
You have it wrong. They failed to signal to the establishment that Romney was unacceptable. And then when Romney was anointed, they failed to walk out of the room.
The Tea Party that I have seen so far is a toothless pussycat and the establishment/RINO party knows it.