Probably a lot of "Bradley Effect" going on here as well.
And while we're at it, being in favor of "abolition", is one thing, but being in favor of it for the wrong reasons is another. Ohio is very labor Union oriented today. Were they against free labor, or were they against the immorality of slavery?
I answered your question. Yes, there were some in the army that cared about abolition before Jan 1 1863. Not many, mind you, but a few did.
As you have pointed out so many time, the reason why, doesn’t matter.
Those people were free to support abolition for whatever reason they chose.