In the end it comes down to two candidates.
if it comes down to three and two of them are ours, we lose.
So we have a primary to hash and fight it out. To decide who we will send against their candidate. We agree to do our fighting against each other then and live with the results.
If a conservative takes his marbles and goes home pouting after this primary, he or she is just, putting it gently, politically stupid.
Refusing to vote for candidate X, but not challenging his legitimacy, is living with the results.
If a conservative takes his marbles and goes home pouting after this primary, he or she is just, putting it gently, politically stupid.
Not necessarily; let's assume that a full 50% of the Republican party decided, as a matter of principal, they would not vote for anyone supporting exceptions [for rape, incest, etc] in illegalizing abortions... if the GOP consistently lost by promoting anyone who supported the exceptions they'd either (a) quit endorsing such people, (b) such people would keep it on the hush-hush, or (c) the party's relevance would decrease.
The only way you have, for certain, to influence party is by support or non-support; providing support when the party violates your core ideals means that the party has no incentive in regarding your core values: they already have your vote.