To answer this question you need to consider the advantages of both the UNion and the Confederacy during the war.
The Union was much more industrialized than the Confederacy, they had a better infrastructure for mass producing goods, transportation, and communication. The Union also had a larger population.
The Confederacy had many strong advantages of its own, they a more experienced fighting force. The South was also fighting a defensive war, the North would have to enter the south to end the conflict. Lastly, the South was fighting to preserve their way of life which resulted in many of them, at least initially, being strongly committed to the conflict.
You ultimately have to answer your own question here but maybe you can consider the information above.
