Heptathlon athlete Jessica Ennis in March at the official British team kit launch for the London 2012 Olympic and Paralympic Games. Warren Little/Getty Images for adidas hide caption

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Many track fans watched online four years ago, as sprinter Usain Bolt set a world record at the Beijing Olympics. This year, NBC will stream video of all 302 events online. And Bolt, seen here showing his appreciation for video in 2010, will try to repeat his feat. Mark Dadswell/Getty Images hide caption

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Archer Khatuna Lorig, seen here during the London Archery Classic last October, helped actress Jennifer Lawrence prepare for her role as Katniss Everdeen in The Hunger Games. Dean Mouhtaropoulos/Getty Images hide caption

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U.S. Olympic Equestrian rider Phillip Dutton jumps with Zeizos in West Grove, Pa., in this 2010 photo. Dozens of horses will fly from America to England for the 2012 Summer Olympics. Don Emmert/AFP/Getty Images hide caption

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Mitt Romney, then the president of the 2002 Salt Lake Organizing Committee, greets attendees at the opening ceremony of the Winter Olympics in Utah. Roberto Schmidt /AFP/Getty Images hide caption

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LaShawn Merritt crosses the finish line first, in the men's 4x400-meter relay at the IAAF World Athletics Championships in Daegu, South Korea, Sept. 2. Once banned for doping, Merritt has been cleared to run in London next summer.

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South African runner Oscar Pistorius, right, runs in the 400 meter race in France, July 8, 2011. His time in a race in Italy Tuesday was good enough to send him to the World Championships. Franck Fife/AFP/Getty Images hide caption

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