As a large multinational corporation, Nike has many advantages over its competitors. Because of its large size, it is able to secure many of the factors of production at lower rates than its competition. This includes the cost of paying labor in factories located in under-developed countries in Asia.
Probably the biggest advantage that Nike has is name recognition. Through careful marketing, and the use of celebrity athletes, the company reaches the important 15-29 demographic. This tradition began with Michael Jordan in the 1980's. Because of name recognition, the company is able to charge more for their products than the competition, which can in turn be used for further marketing.
The scope of the company is another important advantage. The company is no longer just a line of athletic competition shoes. Nike offers a large variety of equipment, running gear, branded clothing, and uniform options. The variety of product allows Nike to reach a large customer audience, which in turn, increases revenue.
Video on the Globalization of Nike, YouTube reference link.