Our southern colonies were largely agrarian and rural while the northern colonies were much less so.
Founders such as Jefferson, Madison, Monroe and many others were Democrats and States Rights advocates since 1775. In contrast, the Republican Party came into existence literally on the eve of the Civil War and promoted strong Centralized Government.
With the election of FDR in 1932, the D's moved away from the southern focus of their values
which championed States Rights, while the R's now championed the middle class and it's values.
It was dual refocusing of what each institution stood for.