Ponting, and others, maintain that the Battle of Britain was a draw. He and they are wrong.
In simple mathematical terms of aircraft destroyed on each side during the battle, one could perhaps argue it was a draw. However, it was not a tennis match.
The vital objective of the Luftwaffe was to obtain air supremacy over southern England which was essential in order that the ground troops could cross the Channel and successfully gain a bridgehead on the South Coast to begin the invasion of Britain. The RAF prevented them from achieving that objective. Without the desired supremacy, or even superiority, in the air the Wehrmacht was forced to call off the invasion.
That was certainly a victory for the defenders and also a significant turning point in the war which, up to then, had been a walk-over for the Axis.