Check out the season finale of American Idol on Wednesday. Carrie Underwood returns to perform her newest single Undo It. Carrie won the competition in 2005 and sang on the Fox series earlier this year. Carrie has not said who she thinks should win American Idol. She said she remembers reading about who celebrities wanted to win during the 2005 season of Idol and says she remembers how hurtful it was. She feels the contestants are under enough pressure.