| Television viewers' first glimpse of Aiken came during the audition episodes at the beginning of American Idol's second season. The show's judges first saw Aiken as a nerdy type unlikely to be any kind of idol, but they were immediately impressed once he began singing Heatwave's "Always and Forever." The clip of the judges' surprise during this audition performance was replayed many times over the course of the competition.
Aiken made it to the round-of-32, but was cut from the show on his first try, a performance of Journey's "Open Arms." He finished third in his semifinal group of eight behind eventual winner Ruben Studdard and eventual third-place finisher Kimberley Locke. However, during the "wild card" round, Aiken's well-received performance of Elton John's "Don't Let the Sun Go Down on Me" propelled him into the final 12. Within the first few weeks (aided by a makeover from the show's producers), Aiken and Studdard emerged as the clear favorites of both the judges and the fans. While Aiken was especially noted for his performance of ballads, such as the dramatically-lit rendition of Neil Sedaka's "Solitaire," his upbeat performances, including The Foundations' "Build Me Up Buttercup," were also met with considerable enthusiasm from the voters.
On 21 May 2003, Aiken came in a close second in the contest, with Studdard winning by a narrow margin--just over 130,000 votes out of more than 24,000,000 votes cast. The result was somewhat controversial as some hypothesized that Idol's voting system was incapable of handling the number of attempted calls, thereby possibly yielding a random result. In an interview prior to the start of the fifth season of American Idol, Executive Producer Nigel Lythgoe revealed for the first time that Aiken had led the fan voting every week from the Wild Card week onward until the finale, when the possibly-random voting result gave Studdard the win. Though officially Aiken was the show's "first runner-up," he has since gone on to be the second season's best-selling star.