I would consider poker: 60%= skills and 40%= luck.
Take for example:
PlayerA has 50% skill and 10% luck. PlayerB has 40% skill and 40% luck. Then surely, PlayerB wins in that instant of time.
I don't think it's possible to find two players of equal skill. Someone's gonna have been more exposed to some situations more than the other player. This is something along the lines of what lgbassman said. The situation can't happen. Even the top players have varying skills. Some of them are better in certain situations than others.