I think it's more complicated than vote tallies. For example, my home state of North Carolina's General Assembly voted to secede unanimously, if I remember correctly, but only did so after all ten other Confederate states had seceded and this new faction geographically surrounded/isolated the state, while Kentucky initially declared neutrality, until Confederate forces invaded, at which time they asked the Union army to drive them out. Maryland and Delaware voted to stay with the Union, but their populations were heavily divided on the issue. Additionally, you had Virginia secede from the Union, and the northwestern counties in that state secede from Virginia to become West Virginia and join the Union. Missouri, another border state, had the government split and so briefly had both Union-supporting and Confederate-supporting factions claiming authority over the state.

I would imagine only the deep south states (South Carolina, Georgia, Alabama, Mississippi, and possibly Texas) had supermajority-level support for secession during 1860-1861, while the border states were more ambivalent about taking that step (Virginia and North Carolina, for example, were not as dependent on slave labor as the deep south, but had some interest in preserving the institution).