David Cook was crowned "American Idol" Wednesday, his smooth showmanship defeating a favored young challenger who swept the judges' praise the previous night.

"This is amazing. Thank you," Cook said, after bending to the stage floor with emotion when the results were announced.

Defeated was David Archuleta, 17, a fresh-faced balladeer groomed most of his life for the stage by his jazz musician father. Archuleta was widely praised by the judges for a slam-dunk performances in the final round.

Cook, 25, who grew up outside Kansas City, Mo., and most recently worked as a bartender while playing in clubs in Tulsa, Okla., was a rocker in the style of one of the show's most successful runners-up, Chris Daughtry.

Wednesday's show, timed to fall on the last night of ratings sweeps, opened with host Ryan Seacrest announcing that the contest wasn't close -- a 56 percent to 44 percent split among the 98 million votes cast, exceeding last year's total by more than 20 million.