Sure - the later half of the Nineteenth Century was pretty dynamic
Interesting. I was thinking mid to late 1862 for the end of the ACW. How this would work out I haven't worked out yet but I will keep this in mind. Thanks.
YAQW. 1862 is probably as "early" as an "early victory" scenario could come into play, given a better result of the US offensive in Virginia.
Have GBM die of typhoid, Sumner take over and wage an offensive from one river line to the next against J.E. Johnston, (Overland Campign in 1862, basically) and I could see the US forces driving the rebels into Richmond by the autumn of '62.
Combine that with the historical US victories on the Mississippi, the Tennessee/Cumberland, the South Atlantic coast, and at New Orleans in 1862,
and leave RE "Granny" Lee rusticating in the Carolinas, and I could see the CSA collapsing in the winter of 1862. There would be plenty of internal recriminations between the fire-eaters of the deep south and the late secessionists in the border states, which would contribute to the "dis-union" (ironically enough) and the eventual possibility of Fusion politics.
One other contributor for an 1862 VC Day: if Grant is left in command after Donelson, rather than being supplanted and then restored to command, it is possible the move south into Tennessee after Nashville will be better concieved and the US forces will be concentrated (under Grant, rather than split between Grant and Buell), so whatever equivalent of Shiloh (Duck River? Pittsburg Landing?) is fought in the spring would be less of a draw and more of an outright CS defeat, along the lines of Vicksburg or Spring Hill/Franklin.
Given that sort of victory, varous "southron" myths will evaporate, and emancipation will come into being in some form.
Given the above, the possibility of a less consensual politics is possible.
The later half of the Nineteenth Century was pretty dynamic politically in the US, probably the one time - because of the varying influences of industrialization, unlimited emigration, and the aftermath of the Civil War - that a relatively "wide" political spectrum could have germinated.
Best,