But yes, 1980 especially was somewhat of an aberration in Massachusetts, as it was only the 7th most Democratic state in the nation that year, after usually being one of the 2 most Democratic along with Rhode Island for most of the last 40 years.
Nice analysis NYM. I've heard a theory that states who have a candidate rejected in the primaries are not enthusiastic for the primary winner. In '80 Ted Kennedy challenged Carter in the primaries and did a lot of harm to his support in MA. I think you can see the same phenomenon in AZ in '00, where McCain challenged Bush, or in KS in '88 where Dole challenged Bush, or CA for Ford in '76, when Reagan lost the nomination. There's ceratinly exception to this-Bill Bradley lost to Gore in '00 but NJ went solidly for Gore-but the theory may explain less than expected vote margins in many cases.