Maybe not a military superpower, but depending on the definition, "a country that has the capacity to project dominating power and influence anywhere in the world, and sometimes, in more than one region of the globe at a time, and so may plausibly attain the status of global hegemony." (Alice Lyman Miller)

China certainly fits that bill, here in South America it has archieved a surprising influence in a very short time, and in Africa it's the dominant power.

During the last two decades, the U.S. influence has been going down in our region, while China's is going steadily up. Today China is the main trade partner outside the region (used to be the U.S. and Europe), infrastructure provider (same), etc...

According to Wikipedia, it's not a "world superpower" yet like the U.S. is, but I definitely think it's going to be one.

http://en.wikipedia.org/wiki/Superpower