COOS BAY — People at the Bay Area Teen Idol semifinals thought they knew what would happen.

 Based on the previous seven weeks’ results, the contestants, the judges and the audience alike could have predicted the three finalists: Alyssa Birrer, Star Moralez and Destyni Fuller consistently have been the top scorers. Mariah Rogers and Caitlin Mansfield would be eliminated.

But when the results were announced Thursday night at the Egyptian Theatre, everyone was surprised.

“Those advancing to the finals,” emcee Mike Chavez began, “are Mariah Rogers ….”

Gasps erupted throughout the theater, and looks of panic spread across the contestants' faces.

“… Destyni Fuller ….”

More gasps. Could one of the two front-runners possibly have been eliminated?

“… Star Moralez … and Alyssa Birrer.”

Organizers had surprised everyone by advancing four contestants to the finals, set for Sept. 20 at the Bay Area Fun Festival.

“You never know what’s going to happen,” contest coordinator Stephanie Kilmer explained.

At the outset of the contest, organizers wouldn’t make public the number of eliminations they planned each week, but they shared one detail freely: There would be three contestants in the final.

Those most surprised by the change of plans were probably the contestants themselves.

“I was really surprised when they called Mariah,” Fuller said. “I thought, ‘Oh no, I’m out!’ But I’m so glad to be going to the finals.”

While the other contestants got a scare, Rogers had a different worry.

“I was really shocked,” she said. “I was freaking out because I thought Alyssa wasn’t going to make it.”

Rogers, 14, said she had mixed feelings about competing in the final, when the finalists will perform three songs each.

“I was planning on not doing any more songs, and now I have to learn three more,” she said. “I’m excited — thrilled and not, at the same time.”

The order of the top scorers wasn’t announced during the show, but Kilmer said Chavez read the top four names in reverse order.

The semifinalists performed songs of their choice in the first round and pop songs in the second, in front of an unusually small crowd of about 200.

Birrer, who also won the people’s choice award for Saturday, sang “Show Off” from “The Drowsy Chaperone,” a tongue-in-cheek show tune about not wanting to perform anymore, and Kelly Clarkson’s “The Trouble With Love.” Introducing her second song, Birrer said she  performed it in the 2006 competition. Judge Kim Handsaker had told her it was too big for her voice at 13, so she wanted to try it again.

“I have a hard time believing I ever said there was a song too big for your voice,” Handsaker told Birrer during the show. “I don’t think there’s such a thing.”

Moralez sang Tracy Chapman’s “Give Me One Reason” and “If I Ain’t Got You” by Alicia Keys, two songs that showcased her soulful voice.

Wearing an American flag-sequined dress, Fuller sang “Letters From War” by Mark Schultz and Amanda Marshall’s “Let It Rain.” Judges Kevin Freeman and Barbara Bates complimented her on singing from her heart.

Rogers sang The Carpenters’ “We’ve Only Just Begun” and “How to Save a Life” by The Fray. She said she surprised herself during the second song when her mind drifted off and she realized she didn’t feel nervous anymore.

Mansfield sang “In My Own Little Corner” from “Cinderella” and Mandy Moore’s “Only Hope.” She all but guaranteed her elimination in the first round when she forgot the words to her song in four places, but she maintained her composure nonetheless. Remembering lyrics has not been a problem for her in the past, and she came back in the second half with a performance that garnered much applause.

One of the contest’s most heartwarming moments preceded the surprise announcement. As all of the contest participants returned to the stage for the last group performance, Birrer invited the children in the audience to come onstage and sing along to “We Are the World.” About 20 boys and girls joined a performance that moistened some eyes in the audience.

“It was a shining moment for the program and the contestants, who are looked up to as role models by younger children,” Kilmer said. “That’s what it’s all about.”