From the 1820's on, the nation was progressively more defined by regional differences and identities.
Instead of Nascar Dads, Soccer Moms, immigrants, etc. the country was divided in a large part by geography with the Northeast, the South and the 'West' making up the primary designations of political loyalty.
The south, Virginia, the Carolinas, Georgia etc. was run by the slave holding old money class of people. Many of the economic reforms in manufacturing and other industries never arrived there, making the landholding aristocracy more powerful and the poorer whites in a constant state of dependence. Blacks obviously were in the ultimate state of dependence there.
The Northeast, New York, Massachusetts, Maine etc. also had an established power structure since it was one of the oldest parts of the country, but it also had a new merchant and business class that was gaining more influence than it ever had in generations past. The improvements to transportation were making it ever richer compared with their southern, more feudal counterparts.
As the value of American currency plummeted during Jackson's disastrous war against the National Bank in the 1830's, the Northeast continued to export and bring in much needed gold and foreign currency into its economy. This kept their economy more stable as the south, which was a net importer of materials fell apart.
The West was dominated by 'new men' from both the south and north. They were speculators, homesteaders and entrepreneurs. They were generally in favor of a strong central government for security against the Indians that populated the land and 'internal improvements' such as rail roads, canals etc. that improved transportation.
Harrison was ultimately a candidate that could appeal on at least two out of three of the levels having been the governor of Indiana a true westerner but having been born in the Tidewater district of Virginia also sufficiently southern. Family title played big in the south and this was the son of a signer of the Declaration of Independence. From the North's perspective, he was attractive because he was not viewed as a complete southerner having made his way in the unsettled lands of Ohio and Indiana.
He also made the Northeast a little more comfortable because although he owned slaves, he was in a large part silent on the issue and didn't challenge the notion that it should not expand and would eventually be fazed out.
To cement his victory in the south however, the Whigs put John Tyler on the ticket. A southern gentlemen that was a sort of Sarah Palin to the ticket. Most Whigs understood he was really a Democrat and not a Whig, but thought that with the upside he'd bring to getting them elected, what's the worst that could happen?
Barely a month after Harrison took office in 1841, they found out.