Glen
Moderator
Upon further review, what the loss of the South might mean is that Adams wins a second term in 1800. So the policies of his previous administration continue. By 1804, however, I imagine the nation might be ready for a change, and Jefferson is still in a position to run, so he wins his first presidency term in 1804 instead of his second term. Some of his actions from his first term are delayed, but he probably plays catch up nicely. Instead of Madison in 1808, Jefferson would likely win a second term. Which brings us a Madison run for his first term in 1812. Would it be against DeWitt Clinton again? In part, that may depend on whether Jefferson has swayed enough votes to get America embroiled in a war with the British (which he might still, though by a whisker rather than a nose as IOTL). The smarter bet might be that there's no declared war with the British, but a Jeffersonian version of the Quasi-war this time against the Brits.
DeWitt Clinton was an OTL Democratic-Republican who was recruited by the Federalists due to his anti-war stand. So no war, he's not the guy, I'm thinking.