Republican governors are common in Massachusetts, it is too bad that Romney finished his term with 34% approval and lost the seat to a democrat after initially desiring reelection until his own polling showed him that futility.
So, the question is, are Republican Governors “common” in Massachusetts. That’s addressed by going to the list. There you will observe that Democrats are equally “common”, and that in recent times several Republican governors served partial terms thereby leading people to believe they were being overrun by Republicans. BTW, William Weld technically counts as a “Republican” in Mass, but he’s actually a RINO. See: http://en.wikipedia.org/wiki/List_of_Governors_of_Massachusetts