This poll is the most apples/oranges poll I have seen yet. While there were versions of the Mosquito built as a "fighter", you would be hard pressed to claim that it would stand beside the Spitfire, Mustang, FW-190, etc as an air superiority fighter. It was an excellent light bomber, recon, ground attack, sea attack fighter-bomber. The P-38 was intended as a long range fighter, that could carry rockets or bombs, but that was not it main role, and it was relegated to that role in the later part of the European Theatre of WWII. The P-38 served as an air superiority and escort fighter in the Pacific till the end of the war. They were both excellent aircraft, but cannot be directly compared any more than you could directly compare the Ju-88 and the Thunderbolt.