Wow...what you say is right on the mark. I live in a state where being anti-abortion is akin to being an Ayatollah (maybe worse!). No Republican could be elected statewide unless they were pro-abortion [rights, they call it], and very few get elected anyway.
We have often failed to be as ruthless and mercenary as RATS, supporting people we don't like and swallowing positions we don't like, in order to get people elected...to sneak our candidates in. Some of that is because of an admirable quality: while RATS are almost always mercenary and self-serving at the core, we tend to believe in principles. The down-side of that is that a majority of the population as a whole either disagrees with those principles or simply doesn't care about anything like "principles". That's especially the case in more urbanized, high population geographic settings.
To say that there are fissures in the Republican party is absolutely true (though this guy mis-identifies them by the bundle). There are as many, maybe more, fissures in the RAT party. But the fissures don't mean as much to the RATS, because they have identified their enemy and nearly always keep their eye on that enemy.
There are probably only about a third of the RATS who really go nuts over Hillary...but were she to jump in to the race the entire party would unite like a whirling dervish behind her. Why? They want to win and they hate their enemy more than any internal divisions they might have.