BEIJING, Nov. 29 (Xinhuanet) -- Eight U.S. Republican presidential contenders on Wednesday night faced a challenge they have never met before -- an unconventional CNN/YouTube debate with videotaped questions that range from the serious to the silly, media reported.

    For the first time, the GOP candidates have to be nimble in responding to video questions submitted by the public via YouTube, just as Democratic White House hopefuls did in July. 

    CNN's political team said they have viewed nearly 5,000 videos for the debate. "Only about 40 will be played at the debate," they added.

    Some of the GOP candidates were reluctant to attend the debate in St. Petersburg, Fla., because they worried the format wasn't serious enough, but a full lineup is expected.

    At the Democrats' CNN-YouTube debate on June 3, a melting snowman frightened about global warming was among the questioners.

    David Bohrman, Washington bureau chief and senior vice president for CNN, said the topics that came up most often for the GOP debate included immigration, conservative values, economic issues and taxes.

    But the clips submitted also included protecting pets, respect for gay and transgendered people, and personal queries such as "What is the dumbest thing you've ever done?" and "How do you know that you won't lose?"

    (Agencies)