The New York Rangers face off against the Los Angeles Kings Wednesday night as the best-of-seven battle for the Stanley Cup begins, and, regardless of who prevails on the ice, the stakes for the National Hockey League couldn't be higher.

There is a feeling that this, at last, may be the year when hockey ceases to be a fourth-class citizen in the world of professional-sports television ratings. A thrilling series of playoff rounds has led to a Stanley Cup Finals involving America's two largest cities. The NHL has reason to hope...