the Northeast went to Carter by a wide margin
Is that really true? Ford won New Jersey, Connecticut, Vermont, New Hampshire and Maine, while Carter won New York, Massachusetts and Rhode Island. It seems as if Ford and Carter more or less split the northeast. It was not the way it is today.
I guess that would depend on whether or not you consider Pennsylvania, Maryland, or Delaware northeastern states. If you do, Carter took them by a count of 99EV's to just 36 for Ford. If you don't, it's 59-36. Others consider Maryland as a Southern state and Pennsylvania as a Midwestern/Mid Atlantic/whatever; I think voting patterns in these states are more similar to the Northeast than anywhere else.