It is precisely because the GOP is a center/right coalition that the GOP is winning, while the kooks and the democrats are crying.
The GOP is not right/center. They are center/left. They want you to believe they are right/center. The only reason most of us vote that way is hopefully we can push the GOP further right. Besides the wot in the middle east, what have they done that's conservative? Spending? Immigration? Campaign finance reform? Smaller government?
It is because the 'big tent' has had space for those who value the RKBA, the lives of the unborn, the sanctity of marriage, smaller government, national security etc., that the GOP has been winning.
ALienate that part of the base, and the GOP will lose its margin against the moonbats.
Take the attitude of "Well, where else are you going to go?" and that arrogance will get you an answer--one the GOP will not like.
As for costing the GOP and the country, if the GOP morphs into the liberal party, nothing is lost which would not be lost anyway. As it is, we have just been going down the same dusty road, only slower.
Mike Pence is right, we need a change of direction.