Who wins after game turns end!

So I know its usually the one with the highest SP collected will win the game if the turns end!

But my question is if I ally with someone who for example had low SP and against 2 with mediocre SP (I beat their SPs individually) but their total is more than the total of mine and my allies' SP, whose gonna win! I am in a game like that now, and I need to know if I should keep that ally, cuz he hasn't done anything all game and his SP is really low, so I would break my alliance with him!

Only you will win... only the person with highest SP wins...

Unless it's a team game in which case, the team with the highest SP wins.