Carrie Underwood sings during a concert for CMT in Atlanta. (Rick Diamond/Getty Images for CMT)

Carrie Underwood has a voice capable of stunning people into silence. It’s a voice that launched the country singer to superstar status not long after she appeared on “American Idol” a decade ago and judge Simon Cowell told her, “Not only will you win this show, you will sell more records than any other previous ‘Idol’ winner.”

Cowell proved prophetic. About 15.3 million in U.S. album sales later, Underwood shattered any expectation of starting out on a reality singing competition. Not only does she regularly sell out arenas and scoop up Grammys, she’s become a prolific Nashville songwriter in her own right, with co-writing credits on half of her 21 No. 1 hits. She co-wrote half of the songs of her fifth studio album, “Storyteller,” out Oct. 23, including her current top 10 single “Smoke Break.”

Yet with all the accolades, Underwood, 32, still somehow flies under the radar. With 29 million digital singles sold, for example, she sits behind Rihanna (100 million), Taylor Swift (93.5 million) and Kanye West (47.5 million), but ahead of Nicki Minaj (25 million), Beyoncé (24 million) and Adele (22 million) — yet she attracts a fraction of the pop culture frenzy. Why is that?

Maybe she’s just not polarizing enough. (When’s the last time you can remember a “Carrie Underwood controversy”?) Maybe it’s her natural inclination as an introvert to shy away from the spotlight. Or, maybe it just looks as if her fairy-tale life and success have come to her so easily that some people don’t think to give her enough credit.

Even now, Underwood says that occasionally — like when she’s on an award show stage in front of her peers — self-conscious thoughts float through her mind. Though at this point, she hosts the shows (she co-hosts the Country Music Association Awards with Brad Paisley for the eighth time Nov. 4). She feels the need to prove that even if she didn’t spend years scraping by as an unknown singer, she still belongs. At the same time, though, when talking about criticism of her “easy” reality TV journey, she describes it as,“I don’t know — a little sexist?”

“What was I supposed to do?” Underwood asks of her career path, which she was unlikely to pursue if it meant playing by herself in bars and clubs on the road. “That’s not my M.O. That would never be my style to get here, anyway.”

After all, singing professionally wasn’t actually her goal. Growing up on a farm in small-town Oklahoma, Underwood had never even been on an airplane when she arrived at the “Idol” auditions in St. Louis in 2004 as a 21-year-old college senior. She knew she could sing; she performed in beauty pageants and talent shows, almost signing a record deal as a teenager. It didn’t work out, so she went to Northeastern State University and majored in broadcast journalism with every intention of going on to a “practical” job.

Those plans evaporated when she wowed the “Idol” judges with Bonnie Raitt’s “I Can’t Make You Love Me” at her first audition and charmed them with an anecdote about playing quarterback for her sorority’s flag football team. They compared her to Martina McBride, and she sailed through the next round. Even as the judges and viewers critiqued her lack of stage presence over the next several months, it was the least surprising “Idol” win ever.

Underwood, the moment she found out she won “American Idol” during the live finale in 2005. (Kevork Djansezian/Associated Press)

About 18 months after her victory, Underwood performs at the 2006 American Music Awards in Los Angeles. (Mark J. Terrill/Associated Press)

“There’s no doubt in my mind that I would not have made it here, without the path of trying out for ‘American Idol’ and without all of that happening,” Underwood said by phone from Nashville of the once-mighty competition show, airing its final season next year amid sinking ratings.

Unlike some reality competitors who sputter out, Underwood moved to Nashville and her career exploded. Five months after she was crowned “Idol” winner, she released “Jesus, Take the Wheel,” written by Hillary Lindsey, Brett James and Gordie Sampson. The song went No. 1 and fueled Underwood’s smash 2005 debut album, “Some Hearts,” which went seven-times platinum.

The experience also started a lucrative partnership with Lindsey. The two first clicked at a Nashville songwriting camp where writers were invited to pitch Underwood songs for her first record. Lindsey remembers Underwood offering her input, but Underwood didn’t start co-writing songs herself until the following year. Together with songwriter Luke Laird, they holed up in her label’s Music Row offices and wrote “So Small” and “Last Name”; both turned into No. 1 hits on her sophomore album.

“Carrie has grown so much as a writer,” said Lindsey, who has nine co-writes on “Storyteller.” Along with James and a few others, they penned much of the record at Underwood’s remote Tennessee cabin. “She’s so smart and really articulate . . . and, clearly, she can sing the songbook. Her lyrics for sure have gotten so much stronger, and they were already strong. You become more comfortable with yourself and in your skin, the more you write.”

Underwood casts a sweet yet tough persona, passionate about topics including animal rights, and speaks often about her Christian faith. (After her much-maligned role as Sister Maria in NBC’s live “Sound of Music,” she tweeted that “mean people need Jesus.”) She’s the everyday wife and mom with a goofy sense of humor, such as her silly CMA Awards skits. She married Nashville Predators hockey player Mike Fisher in 2010, and they have a 7-month-old son, Isaiah. “I think people at this point know we’re boring,” she offers as the reason she doesn’t show up a lot in the tabloids. “We’re a normal couple . . . and we make it a point to raise Isaiah as just a normal kid.”

The characters in her songs, however, tell very different stories.

Underwood and Brad Paisley, who have hosted the CMA Awards together for the past eight years, participate in the Country Music Hall of Fame benefit concert Oct. 6 in New York City. (Evan Agostini/Invision/Associated Press)

Take “Before He Cheats,” about a woman taking a bat to an unfaithful boyfriend’s car; or “Two Black Cadillacs,” in which a wife and mistress team up to kill the philandering husband. On her new album, there’s “Church Bells,” about an abused woman getting revenge; “Dirty Laundry,” centered on a lady who discovers her husband’s affair while washing his clothes; and “Choctaw County Affair,” about a mysterious love triangle. Underwood enjoys writing those dark songs, calling them “mini-movies.”

“I love strong women. I feel like in the characters in the stories, when they’re pushed to their breaking point and they end up winning, they fight back,” Underwood said. “I love that aspect. A lot of times, you don’t make them strong when you’re telling a story like that, until they’re pushed. Usually bad stuff has to happen before they reach that point.”

It’s an especially fascinating dichotomy considering the current trends in the male-dominated country music genre, where women are often supporting characters: in the passenger seat, riding shotgun with their long, tan legs in cutoff jeans on the dashboard. Underwood, frequently cited alongside Miranda Lambert as the only female superstars left in country music, says while it’s clear many listeners love that type of music, she obviously has a different approach.

“I mean, it’s not my style, but you can’t blame an artist or songwriters for doing what they do,” Underwood said. “I feel like, I hope a few artists here and there step up and do something different, which I hope is what we’ve done. And there’s other people who do that as well.”

“Storyteller” also has a softer side, such as “The Girl You Think I Am,” which Underwood wrote for her dad – and which caused many tears during the writing session with Lindsey and David Hodges. Then there’s the quiet final track, “What I Never Knew I Always Wanted,” Underwood’s ode to life with her baby son.

Underwood at the 2015 CMT Music Awards in June at the Bridgestone Arena. (Rick Diamond/Getty Images for CMT)

If history is any indication, any song Underwood releases will inevitably rocket up the country charts. Although seemingly a natural for the pop world, Underwood has never felt any desire to pull a Swift and cross over to a different genre. Instead, she hopes the audiences will continue to follow her in Nashville, where she can help raise the profile of other female artists struggling to break through.

“I feel thankful and grateful that I do get played on the radio, and that I get to headline shows and people come to see them. I think it’s been a great conversation within the past year as far as females in country music,” Underwood said of the much-discussed lack of women on country radio. “So, hopefully, because of that conversation, now some change will happen and more ladies will get a chance. Because they’re out here. And they’re talented and amazing and beautiful and, yeah — they’re out there.”

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