I know it's been discussed before but... well I'm not allowed to bring a topic three years old.
Federal armories are seized by pro-rebel forces who turn them over to the North Carolina government, which to their surprise refuse to secede.
North Carolina refuses to secede from the Union, despite Virginia leaving. The NC goverment do say they will keep the cannons until the conflict is resolved, after which they plan to stay in the Union This leaves them completely surrounded by rebels.
The North Carolina government passes a resolution stated the importance of the union cause, but also says the federal government can't use NC railroads and manpower to bring the rebels back by force without governor approval, which means no drafting either. I think OTL Maryland actually tried something similar.
A secret letter goes to Lincoln saying that they'd love to be 100% unionist, but they are kind of surrounded and believe such a statement would keep the rebels from raiding their plantations, so unless they manage to close 75% of the gap between Union controlled DC and rebel controlled Richmond, trying to force the rebels back seems suicide. So it's not like the Maryland case of conflicting loyalty, but the "we're outnumbered" kind of thing. So if you want to land federal forces in NC by sea, you can't use our railroads without permission, it's not that we don't agree with the cause, it's that we think federal forces using our railroads would result in the rebels getting an excuse to overrun NC. Remember, a Virginia vs NC fight would result in Virginia winning.
Some people of NC do join the CSA, but let's say that the numbers are... 1/30 of the number of OTL men that join the CSA. Some venture to Northern lines to join the Union cuase, same number as in OTL. And the rest of them... well I guess they would sit around in NC and try to continue with their lives hoping the rebels leave them alone.
What happens? Assume that if the CSA try to take NC by force, they don't get additional support from secessionists in the state aside from the previously mentioned ones.
To Clarify; About the title, I don't mean they aren't unionists at heart. They really want the North to win. They just think that allowing use of their railroads or allowing drafting by feds would be a recipe for disaster