Would you vote to bring back slavery or feudalism? This is how bringing back capitalism would go in a functional socialist society.
The level of coercion is about as high as the 14th amendment.
It's probably more a case of all the people who oppose the new socialist system not being interested in participating in its elections, having taken up arms against it or having fled. I imagine people who took arms or offered support to people fighting against the CSA may not be welcome in the voting booth, but that's about it.