We can reclaim it if we primary each an every RINO out of office.
A third party will do nothing but split R votes and ensure a Dem won each and every time.
This where the GOP has gone too far. Through the 2012 election, I was a believer in the 2-party system and said the same things you are saying about "splitting the vote", and how "a vote for the 3rd party candidate is a vote for the democrat". I enthusiastically supported Romney/Ryan by voting and contributing. What has changed? We have seen such brazen betrayal by lying Republicans that I no longer trust them. One of the guys on the 2012 ticket (Ryan) is in full-Rubio mode now!
The GOP used to count on conservatives like me choosing RINOS as the "lesser of 2 evils". However, they can no longer count on such a vote for me. The amount of difference between the two evils is not enough to matter any more. Now instead of saying "a vote for a 3rd party candidate is a vote for the democrat", I say "a vote for RINO is the same as a vote for the democrat". I am no longer frightened about voting 3rd party. If we get more dems than RINOs, it matters little to me. The RINOs in the GOP have overplayed their hand.