Musician Aaron Lewis performs onstage during the Stagecoach Country Music Festival held at the Empire Polo Field on April 29, 2012 in Indio, California. (Frazer Harrison/Getty Images for Stagecoach)

It’s a career reboot that requires more than just a new pair of boots.

In 2008, Darius Rucker, formerly of soft-rock band Hootie & the Blowfish, released a twangy solo album. Today, he’s enjoying another summer on the road as an A-list country star. In April, R&B great Lionel Richie scored his first No. 1 album since the Reagan administration with “Tuskegee,” a batch of his vintage hits reimagined as duets with country A-listers, including Rucker. It’s currently the highest-selling album released in 2012.

But if it looks as if Nashville’s tent is getting bigger, look again.

“The genre is not friendly to newcomers,” says Aaron Lewis, the latest refu­gee to set his sights on the country charts. After 16 years spent fronting the multi-platinum rock group Staind, Lewis released his first solo EP last year, a collection of country tunes called “Town Line.”

Supportive Staind fans quickly pushed “Town Line” to the top of Billboard’s country albums chart. Its first single, “Country Boy,” featured guest turns from country royals George Jones and Charlie Daniels and was nominated for prizes at the CMT and ACM awards. But radio wouldn’t touch it. Dyed-in-the-denim country fans kept their distance.

Singer-songwriters Kenny Rogers (L) and Lionel Richie perform during Lionel Richie and Friends in Concert presented by ACM at the MGM Grand Garden Arena April 2, 2012 in Las Vegas, Nevada. (Ethan Miller/Getty Images)

“It hasn’t been easy in any way, shape or form,” says Lewis, who performs at the Birchmere on Tuesday. “The biggest thing that I run up against is, ‘He’s not country.’ . . . It’s frustrating.”

Alison Bonaguro, who writes about country music for, says it’s typical. Despite the unlikely triumphs of Rucker and Richie, the industry isn’t rolling out red carpets for any old artist hoping to hit reset in Nashville. “It’s not as hospitable as you’d think,” Bonaguro says. “I think there’s a little clique-iness, [a feeling] that it’s almost not fair that there’s so many people wanting a piece of that pie.”

If Lewis wants to score a slice, his upcoming album, “The Road,” due out Sept. 11, will have to resonate with fans and radio programmers the way Rucker’s 2008 solo debut did.

Other outsiders haven’t had the same good luck. In 2008, pop singer Jessica Simpson’s country debut, “Do You Know,” debuted at No. 1 but quickly vanished from the airwaves. She left her label a year later. Meantime, Broadway singer Laura Bell Bundy has fared even worse. Her 2010 country disc, “Achin’ and Shakin’,” failed to make a noticeable dent on the charts.

That might be because, fabricated or not, credibility is still a leading virtue in country music. During his promotional tour for “Tuskegee,” even Richie had to to prove his bona fides. “I was born in the country, country radio was radio when I was growing up,” the Alabama native told CNN’s Piers Morgan in an interview televised in March. “I’m just going back to claim my kids.”

Lewis has a similar story. The 40-year-old singer grew up in Massachusetts but spent his summers listening to country music with his grandfather. For him, this isn’t a reinvention so much as rediscovery of what’s always been there.

“I write music on an acoustic guitar,” Lewis says, citing “It’s Been Awhile” and other slow-churning hits he penned for Staind. “If I had brought those same exact songs to Nashville and colored them country, they would be right in line and right on point with the stuff I’m working on now.”

But Lewis says the stylistic shift has also freed him up to write more upbeat material. His latest single, “Endless Summer,” feels worlds away from the sepia-toned angst of Staind, even though it centers around something potentially more distressing: a family car trip to the beach.

“That’s definitely a happy song,” says Lewis. “And it’s definitely a song I could never ever, ever have brought to Staind. It just wouldn’t have worked.”

Now, in an effort to get “Endless Summer” on the radio before summer ends, Lewis is lobbying Staind fans to “torture” the nation’s request lines, hoping to make country fans of them in the process.

“A lot of them had never, never listened to country before,” Lewis says of his flock. “Now, they’re branching out into country and growing an appreciation for it. And they’d never have given it a chance.”

But even if he brings new ears to the genre, the blanket skepticism that so many country fans reserve for outsiders remains a huge obstacle. It all reminds Bonaguro of “Gone Country,” a 1994 song by Alan Jackson that takes a jab at musicians looking for a shortcut to stardom by way of Music City:

He’s gone country/Look at them boots.

He’s gone country/Oh, back to his roots.

“That’s an old song, but God, it’s still so true,” says Bonaguro. “For some people in the industry, it’s a philosophy.”

Aaron Lewis will perform at the Birchmere in Alexandria on July 24 and at Ram’s Head Live in Baltimore on July 25.