I think the election of Hillary could be the spark. Just like LBJ/Goldwater was the spark that caused the GOP to eject the Birchers and others. The only thing uniting the GOP is their dislike for Hillary. With the Dem's lead in the electoral college, a win by Hillary could be the spark to throw the GOP into complete disarray. The desire to win national elections versus winning gerrymandered Congressional districts will end being to root.
I could see that. But, I think that would largely depend upon the GOP candidate, and how much blame could be laid at his (no prospective hers atm) feet. If the election is a close one, they might yet blame the candidate's strategy and the role of his conservative credentials might be debatable. If Hillary wins handily, then yes, I could see that happening. IMO real pressure will befall the GOP after the next census. Gerrymandering enabled them to consolidate electoral power, and significantly contributed to their ability to take Congress. However, the population is changing, and the new district maps will likely demand that the GOP move back towards the center to hold as many congressional seats. No doubt, the Tea Party faction won't want to make that move.