Michael Phelps' eight gold medals could be worth eight figures in endorsements and earnings, experts say.
"If he's handled properly over the next four years, he should generate in excess of $40 million," said Marc Ganis, president of Sportscorp Ltd., a Chicago-based sports business consulting firm.
"If he's handled properly over the next four years, he should generate in excess of $40 million," said Marc Ganis, president of Sportscorp Ltd., a Chicago-based sports business consulting firm.