more chance - I think its better to use "a greater chance of winning" bigger/smaller chance (I think they are okay too) "a lesser chance of winning" You can use "small chance" with a small difference in meaning. There is a small chance of winning the game if you guys can work as a team. If you guys don't work as a team, you all will have a lesser/smaller chance of winning the game.
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.