The Whigs did have majorities at certain points in FL, GA, KY, LA, MS, NC, TN & VA, so the Jeffersonians/Jacksonians weren’t without a challenge. John C. Calhoun passed on leading SC Nullifiers into the Whigs (although his fellow Senator William C. Preston did) and returned to the Dem fold.
Of course, there wasn’t a gargantuan gulf ideologically between the two groups as we have today between the present parties. The Dems had their anti-slave factions and the Whigs had their pro-slave “Cotton” faction.
But in those days, the folks that could vote all had proverbial skin in the game and making a mistake could cost them everything. Except to the truly radical, it was unimaginable for them to saddle the nation with such debt and spending, even in the case of emergencies.
However, in the post-Civil War period, you did start to have leftist economics rearing their ugly head under the so-called populist movement, the free-Silverites and the like, and they did include Southerners. Many Southern Democrats were behind the push for bigger government, especially in toppling the Conservative Bourbons (the fiscally responsible Dems). All 4 of the post-Civil War Dem Southern Presidents (Wilson (I count him as Southern despite being elected out of NJ), LBJ, Carter, Clinton) have all been left-wingers.
Speaking for my fellow Southerners....we don’t count Wilson. He was a New Jerseyite as far as we’re concerned. Yes we know he was born and raised in Virginia but he left and his views were much more in line with New Jersey where he lived for many years and worked and first was elected to political office.
LBJ, Carter and Clinton were all Democrats from the 60s on. By that time the party had drifted way to the Left. LBJ implemented really big expensive social programs and post LBJ, the more hawkish wing of the Democratic Party was completely destroyed. There was absolutely nothing left that would appeal to Southerners. Frankly, I’m surprised it took until 1992 for the South to finally send more Republicans to Congress. Old habits are hard to break I guess.