NEW YORK (AP) -- Soon, maybe just weeks from now, federal prosecutors likely will need to make a choice. They either stop chasing seven-time Tour de France winner Lance Armstrong, or they present a charge that ties one of the world's most famous athletes to drug use.

It's a decision that involves more than simply weighing the evidence.

Armstrong's popularity, his wealth, his ties to powerful figures including former U.S. presidents, his vehement denials, scores of clean drug tests - and, above all, his status as a cancer survivor and advocate for eradicating the disease - make him an incredibly tough target.

But for those who believe Armstrong cheated, all of those obstacles are less important than proving his guilt and striking
perhaps the biggest blow to date against performance-enhancing drugs.

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