communist spain

In our timeline the Carlists managed to win the Spanish Civil War. But what if they were defeated and the Republicans, the Communists, or the Falangists had won? How would this Civil War had been different, and how would Spain have been shaped in the 20th century when WWII rolls around?

Pick any POD you want (can be before or after WW2). What's the best way for Greece, Italy and Spain (maybe also Portugal) to become communist at around the same time? If there's any way it could happen during World War 2, what impact would it have on the war? If this can't happen, then what...