Prove it.....
I know my own state passed secession by popular vote, overwhelmingly!
Not even a majority of white men could vote in the pre-Civil War South. It was the Reconstruction-era state governments which extended the suffrage to all men in the South, white and black.
In those days, balloting was done in public, so it took a VERY brave man to vote against secession, at a time when the state governments, the militias, and the police were already controlled by rebels. Generally, the poorer a southerner was, the more likely he was a Unionist and less likely he had the right to vote. Also, a third of southern men, the blacks, could not vote in the pre-Civil War South -- and they would have been solidly against secession -- so it is just wrong to claim that a majority of southerners favored secession.