What singer made appearances during Keith Urban's Ripcord World Tour who also the winner of the  fourth season of "American Idol"?
Carrie Underwood Carrie Marie Underwood (born March 10, 1983) is an American singer, songwriter, and actress. She rose to fame as the winner of the fourth season of "American Idol" in 2005. Her debut album, "Some Hearts", was released in 2005. Bolstered by the huge crossover success of the singles "Jesus, Take the Wheel" and "Before He Cheats", it became the best-selling solo female debut album in country music history, the fastest-selling debut country album in Nielsen SoundScan history and the best-selling country album of the last 14 years. Underwood won three Grammy Awards for the album, including Best New Artist.
American Idol (season 7) The seventh season of American Idol, the annual reality show and singing competition, began on January 15, 2008 and concluded on May 21, 2008. Ryan Seacrest continued to host the show with Simon Cowell, Paula Abdul, and Randy Jackson returning as judges. David Cook was announced the winner of the competition on May 21, 2008, defeating runner-up David Archuleta by a margin of roughly 12 million votes out of over 97 million, which was at that time the highest recorded vote total ever recorded in the show's history. The split was 56 % to 44 %.