I knew it was either Surge or Blaine, and I didn't see the Surege episode... hence I voted Blaine.
IMO, if you defeat a gym leader after loosing, it's still legitimate. But Ash only beat Blaine becuse they swapped the stadium where the gym battle was held, if anybody remembers. Then 2nd time, it was up ontop of a lava field again, but it was outside, and the floor was more like Rocks shooting out of the lava, and the Pokémon had to stand on the little areas. [Gives Charizard the advantage, because all it has to do is fly around. >.>] So, yeah... Surge wins I guess.