Political momentum usually plays a big role in this kind of movement and that was of course true when our own Constitution was ratified. In some of the latter state ratifying conventions, proponents could argue with some force that ratification was necessary just to avoid being left out of the Union.
So, I think that the early "secession" states like South Carolina played a pivotal role in the southern "secession" movement. In post 89, I criticized Governor Pickens for visibly painting himself into a corner before the state's convention session met. But, as I also mentioned, Pickens had just been chosen to be governor by a secret vote in the South Carolina legislature and the reality is that he probably emerged from that process with very little remaining political range of motion on the question of "secession." All of this suggests to me that the "secession" convention in December, 1860 was little more than window dressing for a political decision that had already been determined with a strong sense of finality.