re: Why doesn't the GOP attempt to "fracture" the DEM party?

Honestly? You cannot fracture chaos driven by an ideology. All of those under their tent believe that they will all (eventually) achieve their desired endstate, even though they are often diametrically opposed to each other. I give the Democratic Party tremendous credit, they do a great job of convincing all of their constituents that life will be great when they (finally) reach Nirvana. You can show them the abject failures of their party leadership/single party rule (e.g. Detroit) and they will still say "But if" or "They did" and the adherents will still believe. Along the lines of (secular-humanist) religious fervor/hysteria.