I think if the Hurricanes replaced all the Spitfires we still would have won. It was the Luftwaffe's change of targets that saved the RAF in the south. The Bf-109E didn't have an easy time with the Hurricane, far from it. And the fights would still take place around the bomber formations leaving the Hurricanes open to attack the bombers while the fighters tried to get them away.
Yes, in my opinion, if the Spitfire squadrons were made up of Hurricanes instead we could have still won. The same applies, in my mind, to the opposite with Spitfires. If Spitfires were all we had, in the same numbers as Hurricanes, we could have won.