Another reason
why Nationalist is stronger than the republicans is due to it having the Army of Africa, a combination of Spanish and Moroccan troops this army is known this army is known to experience combat during the Moroccan conflict thus having experience in the battlefield. This means that the nationalist have a combat experience army on at its disposal adding to the fact that the nationalist was stronger compared to that of the republican.
Republican also has advantages, mainly on the territories they occupy. The republican still have control on Spains two major cities, Madrid and Barcelona. Both cities have a population over a million thus giving the Republicans an advantage in terms of manpower. The republicans also have control over Basque and Asturias, meaning they have access to raw materials, leading to them being able to better equip their militaries. The republicans also gained support of the navy and air force adding more to their military power.