Athens is hosting the event because Greece won last year in Kiev, Ukraine.
The show opened in true Eurovision style, with a garish musical number inspired, organizers said, by Greece's rich history, mythology and sparkling seas. The hosts, Greek pop singer Sakis Rouvas and American Access Hollywood correspondent Maria Menounous, were flown in from the wings onto a set inspired by an ancient theater.
Broadcaster NBC announced plans earlier this year to replicate the formula -- a forerunner of American Idol-style talent contests -- in the US, with acts from different US states competing for viewers' approval.
The European Broadcasting Union, which runs Eurovision, said it was in talks with NBC over rights. If successful, the American version could go ahead as early as this fall, said the group's director of television, Bjorn Erichsen.
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