Yeah looking at the record the Establishment republican always wins, in fact the democrats in picking Obama, Clinton, Carter and Mcgovern appear to be more likely to pick an anti-establishment candidate
2012-Romney, establishment candidate
2008-Mccain, heir to the nomination, relative establishment apart from Giuliani (who imploded)
2000- Bish, definition of the establishment.
1996- Dole, senate majority leader, need I say more?
1992- Bush, VP and saw off right wing challenge.
1988- Bush, again establishment
1980- Reagan, may be the only anti-establishment but still heir after 1976 and weak field
1976- best chance at winning as an insurgent, but Ford still won
The establishment is getting weaker every four years. Romney with a huge endorsement and dollar advantage only barely was winning until brute force took his opponents out of the race. If Santorum and Gingrich hadn't divided their own conservative base, Romney might have lost. Even after they were all out, Romney was still under <70% in California and Texas uncontested and gave up 40% to Ron Paul as the only other option in Virginia.