Earlier quoted context omitted.
Do you have data on slavery? My understanding was the North was pretty anti-slavery and had 3x the population of the south. I'd be interested if there is actual polling data to suggest if a popular vote was held it would have failed.
I thought part of the point of the strange election process we have was to "ensure" that southern states would have a vote even in the face of a more populous north…
In fact, it was the slave owning southern states that wanted the Senate to be apportioned proportionally, rather than equally (this was the Virginia Plan). The Virginia Plan created a two-chamber legislature with proportional representation based on population. The New Jersey Plan would have allocated one member of Congress to each state. The Connecticut Compromise that led to the current allocation received buy-in from both slave and non-slave states, because it was about small vs large states, which were present in both sides.
The population advantage of the South was the impetus behind the infamous "three fifths compromise". The 3/5 compromise was designed to reduce the interest of slave-holding states in Congress as well as the elections.