Transcript for Who Is the Most Fascinating Person of 2015?
Reporter: And finally, our choice for the most fascinating person of the year was once called the world's greatest athlete. Traditionally, that title was given to the man who won the olympic decathlon. When Bruce Jenner won it in 1976, it was a huge accomplishment. It had everybody talking. But it was nothing like this. When Bruce Jenner became Caitlyn Jenner, there was a seismic shift in the gender universe. Caitlyn! Reporter: If you found yourself unable to take your eyes off Caitlyn Jenner this year, you weren't alone. The transformation of Bruce Jenner, who performed heroic feats of endurance and winning the olympic gold medal for the decathlon, into Caitlyn Jenner, who performed heroic feats involving hair extensions and eye makeup was fascinating. Jenner explained it this way. For years and years, I never felt like I fit it anywhere. I always felt as an outsider. I never felt good in the male side, and I wasn't, obviously, in the female side. I was kind of stuck in the middle. Reporter: Jenner certainly didn't seem like he was in the middle. He became famous for winning the olympic gold medal in 1976. Bruce Jenner. The guy on that day was the person to be able to do that. And so in that way, that uniqueness is something that makes you feel good. I mean, it makes you feel like you really accomplished something in life. At a price you never thought you could afford. Reporter: For the next years, he marketed that accomplishment as a celebrity endorser. Exhale. Hi, I'm Bruce Jenner for tropicana. Get whole wheat wheaties working for you. Remember, there's only one stair climber plus total workout system. Reporter: Then married Kris Kardashian who marketed him, her kids, and their kids on "Keeping up with the kardashians" till their public breakup last year after 24 years of marriage. Jenner's transition took place partly on her own E! Reality show, "I am cat." On it, she indulged in all things girly. My god, look at all this stuff. I know. So let me see your purse. Reporter: She fused endlessly with her appearance. There were hugs. Everybody on Jenner. Reporter: And hugs. And even more hugs. And many girlish toasts. And more hugs. But beyond the reality show conventions. Road trip! Reporter: A larger question lurked. What is gender? What was the real difference between Bruce and Caitlyn Jenner? She still liked motorcycles and golf. She was still attracted to women. Could it be any more complicated? Reporter: And sometimes, in painfully honest moments from her show -- Oh, my goodness. Reporter: She still seemed like, well, like a clueless guy. I didn't want to communicate with you and be angry. What would you be angry for? One of the things I always used to notice was that Bruce wasn't as sensitive as I wished he was. I used to chalk it up to the fact that he was a guy, but I'm realizing now that maybe that's just bruce/caitlyn's personality. Reporter: She was a lightning rod for criticism. Ladies and gentlemen, Caitlyn Jenner. Reporter: First for the courage award that ESPN gave her. Does she deserve this award? For what? I mean, self-definition is what you do. I wasn't aware that you get a medal for it. Reporter: Then for the glamorous style of her transition. Caitlyn Jenner does not walk in the shoes of those young transgender youth because they don't have the means that she has. Jenner's transition has been one of privilege. Caitlyn! Caitlyn! Reporter: The Caitlyn celebrity brought new attention to the grim reality of life for many transgendered people. India Clarke is the tenth transgender person to be murdered. 40% of transgender youth have attempted suicide. Reporter: Caitlyn educated herself. Hello, everybody! Some people are very cruel, not accepting. It's extremely important that we're heard. Reporter: She became a champion for people who had long been pushed to the margins of society. Maybe this is why god put me on this Earth -- to tell my story, to be authentic to myself about who I am, and maybe, in doing that, maybe you can make a difference in the world. What a great opportunity in life to have. Reporter: Famous and familiar, she raised awareness and acceptance of transgendered people. Through her own transformation, Caitlyn Jenner transformed society this year, and that, for us, makes her the most fascinating person of 2015.
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