Ellen DeGeneres' discovery on YouTube of two British cousins -- who loved to sing and dance in pink frilly dresses -- marked "the beginning of a beautiful friendship," to borrow from Humphrey Bogart in "Casablanca."
In this case, the friendship that blossomed was between "The Ellen DeGeneres Show" and YouTube, the popular video website owned by Google.
Executives at YouTube and Warner Bros., which produces DeGeneres' afternoon talk show, pinpoint the first appearance of the pint-sized crooners, Sophia Grace and Rosie, on DeGeneres' show in late 2011 as a spark that helped ignite DeGeneres' social media supernova status.
DeGeneres' channel on YouTube has attracted 1.7 billion views -- more than three times the number of the second most popular TV celebrity, ABC's Jimmy Kimmel.
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"Ellen has this amazing relationship with her fans and it extends to YouTube," said Paul Snow, YouTube's manager of entertainment content partnerships.
"And videos on YouTube are helping to inform her decisions on how to program her show," Snow said, adding that DeGeneres and her producers at Warner Bros. have been leaders in figuring out how to mine the Internet to benefit a television property.
Last month, DeGeneres' show brought a 4-year-old boy, Kai Langer, from San Antonio to Burbank, where he performed the Bruno Mars hit "Grenade" on her show. The clip has been watched more than 9 million times, turning the tot into an Internet celebrity.
"He was out there on YouTube but Ellen and her team was able to really shine a spotlight on him," Snow said. "Ellen goes for cute but she also has this amazing curation, tastemaker component to her show."
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DeGeneres' YouTube channel, with her Twitter messages and Facebook page, have helped to expand DeGeneres' following among young audiences. Her show ratings have increased 10% this season among women ages 18 to 34 as compared with the previous season.
"We are using social media to attract the next generation of Ellen's fans," said David McGuire, executive vice president for current programming at Telepictures Productions, which produces DeGeneres' show.
The YouTube channel also created a lucrative source of revenue for the television show, which shares advertising revenue with YouTube.
"It began as a promotional vehicle but it grew into a business," McGuire said.
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