No..oro couldn't win vs Madara unless he returned with some power boost (dragon sage)?
Madara is by far superior not because of Rinnegan or Mokoton but because he was able to break his own Edo Tensei contract and practically revive himself..DSM Oro might have a good chance tho, Oro was always intelligent enough to go vs the best, however he did get owned by Itachi's genjutsu..and I can only imagine Madara's is far superior to Itachi's
Madara also knows more about the Uchiha secrets then anyone else, I say this with confidence because for one he has Rinnegan, giving him the ability to read the So6P Tablet that was left to the Uchiha, two he has/had Tobi, getting into the Village to read it after gaining Rinnegan wouldn't of been hard
As far as Tobi goes I don't think he stands a chance vs Madara, he obviously fears Madara as seen when Kabuto showed him Madara's body, the original plan was to have Tobi give Rinnegan to Nagato to later Rinne Tensei Madara back to life, Tobi obviously didn't follow this plan out of fear of Madara's return and decided that Madara's name alone was so powerful that he would just claim to be Madara himself
Naruto or Sasuke will be the one to fight/seal Madara in my opinion, Orochimaru's scroll that was found might play a huge part in it but over all it will be one of those two who defeat him