Who Would Win?
I've taken a survey of the previous Superman vs. Thor opinions (mostly from YouTube), and the outcome is that Thor could best Superman in a one-on-one contest. The contest revolves around Thor being a magical being and the fact that Superman has two weaknesses, i.e., kryptonite
and magic. Since Thor is an entirely a magical being, Superman would be at an immediate disadvantage. Whether any of Superman's powers would be effective against Thor is pure guess-work. Most probably his powers would be rendered useless. In a sense this would be like a contest against Superman against Dr. Fate. Superman is the supreme being on earth, but he is susceptible to the supernatural. Characters like Dr. Fate or Dr. Strange could simply put Superman in another dimension (like the Phantom Zone) from which he would be powerless to combat. The decisive point in a collision between Thor and Superman is the extent to which Thor's supernatural abilities would effect those of the man of steel. If Thor were any other mortal, Superman could slice him into two with his heat vision or create a vortex around him using super-speed, but Thor originates from another dimension and none of these tactic would be effective. Superman would be powerless against Thor's hammer, and that alone would be enough to render Superman stupefied. The good news is that Superman and Thor belong in different publications, and unless DC and Marvel decided to try a cross-over, both heroes have nothing to fear except their usual adversaries. Secondly, a contest between Thor and Superman is unlikely to take place since they both fight on the side of good against evil.