In 1944, members of the Unión Nacional Española, mostly communists from the PCE after the Allied liberation of Southern France tried on October 19th to invade Spain from France with 5,000 soldiers/maquis.
However they utterly failed, being driven back by 50,000 Francoist soldiers led by José Moscardó. Is there any possibility for them to succeed? Or to be somehow backed by the Allies? If so, what would be consequences of a liberation of Spain?