Thousands of biathlon competitors and fans have gathered in rural Aroostook County in Maine for the sport's World Cup. More than 10 years ago, Aroostook, traditionally a hub for potato farming and logging, hatched a plan to reverse the stagnant wage growth and high unemployment that plague so many sparsely populated areas. The county already drew large numbers of snowmobilers to its network of well-groomed trails. So Aroostook set out to build on that base — by capitalizing on its long history of superb cross-country skiing and transforming itself into one of the world's premier Nordic sports destinations.