That is rather fraught question and one that, to some extent, reads the sectionalism of the Civil War back in time. For much of colonial and early republic history, you can find as much difference between adjacent colonies/states as you can between the north and south. The answer also depends by whether you're asking about social, economic, or political distinction. Socially, there were significant demographic differences in the colonies: fewer enslaved people lived in the northern North American colonies (though many did), and people generally tended to live longer in New England than they did in the Carolinas/Chesapeake (New England is credited, a bit as a joke, with inventing grandparents). Economically, by the 1770s, both the north and south were primarily agricultural societies. Their crops differed as a result of climate and soil, and the organization of farms differed, too (small farms predominated in northern colonies, while the south was tending toward large plantations). Overall, however, most people--north and south--engaged in agriculture or related fields. Politically, major sectional differences over slavery were not pronounced until the 1800s. There were minor disagreements, which can be viewed as northern/southern distinction, in the crafting of the Constitution. Most of these were settled through compromises, such as the 3/5s clause to limit southern representation in congress and the eventual closing of the slave trade in 1807. Around the time of the founding, many people, north and south, expected slavery to die a slow death in the late 1700s and early 1800s, and they did not see it becoming a huge problem of sectional distinction. The invention of the cotton gin, coupled with the expansion of territory under the Louisiana Purchase (1804) and the subsequent expulsion of Native Americans from the territory that would become Alabama and Mississippi, brought the first ripplings of sectional tensions over slavery. Suddenly, with the expansion of cotton, slavery took on a renewed importance. This culminated in the Missouri Compromise (1820), which is seen by many historians as a harbinger of the sectional conflict.

An older, but still quite good and useful book for understanding the similarities and differences in the development of the North American colonies is Jack P. Greene's Pursuits of Happiness (Chapel Hill, UNC Press, 1988). It challenged the long-standing assumption that the New England colonies were the incubator of a distinct "American" culture. Greene, instead, shows that NE was unique compared to other British American colonies, and he argues that American culture had much more to do with Virginia than NE. He also suggests that, though the colonies followed quite different models for settlement and development, by the 1770s they were converging rather than further differentiating.

tl;dr, I'd suggest there wasn't much meaningful distinction between the northern or southern colonies/states by the 1770s. The factor that contributed most importantly to sectional divide by 1860, however, would be slavery as an economic and political institution.