American Idol winner Carrie Underwood (search) is becoming a Nashville idol.

Underwood was set to perform on the first day of the Country Music Association's (search) annual festival Thursday in a lineup that included stars like Dolly Parton, Keith Urban, and Lee Ann Womack.

"I'm from Oklahoma and grew up listening to country music. I think it's the most cheerful music," said the 22-year-old singer.

On American Idol, Underwood sang songs by Rascal Flatts, Martina McBride, the Dixie Chicks and Shania Twain. She was crowned in May after performing the Rascal Flatts hit "Bless the Broken Road."

The last time she attended the CMA Music Festival, Underwood said she was 15 years old and waiting in line for autographs. Now, people are waiting in line to see her.

Thousands of fans arrive every year at the CMA Music Festival to listen to live music and get autographs from artists. The festival runs through Sunday.

On Saturday, Underwood was scheduled to make her debut on the Grand Ole Opry (search) radio show. She admitted she felt a little anxious about the Opry appearance.

"It's such a sacred place. So many people have played there," Underwood said.

On Wednesday she had taped an upcoming special for Country Music Television, performing the Reba McEntire/Linda Davis hit duet "Does He Love You?" with Jamie O'Neal.

This fall, she hopes to release a country album.