Ulcerated underbelly?
Then Spain and Portugual are firmly in Napoleon's camp, without the bleeding ulcer
Why? The Spanish Ulcer would still have ulcerated Napoleons soft belly in Spain. Many troops would still be needed to tie down the affected areas where the uprisings occured. This was by no means the first anti-invader uprising, but it was the one that gave wing to the ideal that you do not accept the tyrants boot on your neck - who ever you are, and whoever the tyrant is. Spain for the Spanish and all that. Sure the war was successfull with the British (and allied) army to provide an anchor; but that anchor was set in shifting sands. The British army was never in occupation in all areas of Spain, indeed for many months of the conflict, it wasn't even IN Spain. Many deride the performance of the Spanish army, but like any army bereft of a central command, and denied its own logistical, training, and traditional base, it struggled. However, it succeded where the Prussians did not in 1807, it bested the Austrian defences of 1809, and came half way as close to the success the Russians had in 1812. Sure they got beat whenever they stood, but they stood time and time again. A better result than the Americans had in the war of 1812, when the USA retained their central command and control, logistics and traditional base. A better result than could be expected for a headless collection of a multiplicity of field commands. Now add the effect of the British and allied army, and the war based on "interior lines" and you will have an ulcer, big or small, it's going to hurt!