Gotta go work out, MT. Will return to this later. Just a note though; look at the platform adopted by the Dems in June, 1860 and tell me where it's anti-slavery.
Back later, but for now:
The intensifying sectional conflict signalled by the Dred Scott decision helped to splinter the Democratic party into three factions, each of which nominated a candidate to oppose Lincoln. Northern Democrats generally supported Stephen A. Douglas, Lincoln's old rival from Illinois; the "Little Giant" supported the notion of "popular sovereignty" and opposed a move by Southerners to include a repressive slave code plank in the Democratic platform.
After Douglas' nomination, a group of Southern delegates left the Democratic convention and adopted their own, more stringent proslavery platform. They eventually nominated John C. Breckinridge, Vice President of the proslavery Buchanan administration.
An effort to reunite the Democrats at a new convention failed when Douglas supporters blocked a move to readmit the Southern "bolters" who left the first convention.
he more moderate Southerners, claiming a power base located mainly the northern areas of the South, called themselves the Constitutional Union party and nominated John Bell of Tenessee on a platform calling for preserving the Union and enforcing its laws.
Despite the fact that the Republicans nominated Lincoln precisely because he was the consummate moderate on the issue of slavery, and therefore stood the best chance of carrying critical Northern states... .
... With only about 40 percent of the popular vote, Lincoln garnered 180 of the 303 electoral college votes, a testament to the comparative power of the Northern states. The splintering of the opposing party undoubtedly contributed to his victory; if the Democrats had pooled their votes, they may have been able to swing a sufficient number of Northern states their way.
Looks to me like the Dems self-destructed which undoubtedly helped Lincoln win. Remember, however, that Lincoln was the "moderate" on slavery.
So if you're going to make the case that the slavery issue fractionated the Dems, giving Lincoln, a moderate on slavery the White House and THIS caused secession... well, I can see the train, but I think it's a bit of a reach and ignores the State's Rights issues that underly the ENTIRE situation.
Again, look at the changes made to the US Constitution in the Confederate version. I think that tells you where THEY, the secessionists, think the problem was.
Off to work out. Later.