"It's been a run. ... No. 11 out of all them people is more than I could expect," she told host Ryan Seacrest.
Carly Smithson and Kristy Lee Cook were the other lowest vote-getters.
Cook, a 24-year-old from Selma, Ore., has been a bottom-three fixture in the past weeks and the finalist that judge Simon Cowell picks on the most.
Cowell -- who has called Cook "forgettable" and compared her voice to "Dolly Parton on helium" -- continued his harsh criticism Tuesday after the country singer's take on the Beatles' "You've Got to Hide Your Love Away."
"(You're) like musical wallpaper, insomuch as you notice it, but you can't remember it," he said. "And that's what you're doing week after week: You're making no impact."
Cook talked back to the acid-tongued judge, saying: "I can blow you out of your socks, and you know it."
Wednesday's "Idol" featured a performance by season-five finalist Kellie Pickler.
Seacrest also announced this year's roster of celebrity mentors: Parton, Mariah Carey, Andrew Lloyd Webber and Neil Diamond.