WATERLOO -- Skillet may be one of the best-known bands you've never heard of.

The Tennessee rockers snagged a Grammy nomination in 2005 for their album "Collide," and their 2006 hit, "Rebirthing," receives steady playtime on radio stations across the nation.

Still not ringing a bell? That's because the Christian group, formed in 1996, is just starting to break into the mainstream music industry.

The band is hoping to expand its name recognition this fall on tour with Breaking Benjamin, Three Days Grace and Seether. On Friday, Skillet warms up McElroy Auditorium as it attempts to rock in the secular world without losing its religion.

"It's been a long time since we've played in front of new people," said front man and songwriter John Cooper. "We've been doing our own touring for so long and most of the people we play for are fans. This lets us get our music out to more people."

The decision to go mainstream coincided with a shift in the subjects tackled by the group. Gone are the praise ballads gobbled up by devout fans in the '90s. Skillet's last two albums ("Collide" in 2004 and "Comatose" in 2005) address suicide, family fights and drug abuse.

Skillet's early songs targeted believers and didn't appeal to those who prefer to sleep in on Sunday morning, said Cooper, 30.

"But in the end, we are all going through the same things as people -- Christian, atheists and in-between -- and I wanted to write songs about that," he said, noting that God is not gone, but nuanced in his latest lyrics.

Skillet will play for 20 or 30 minutes Friday. It's worth a listen.

After putting in its hard-rock dues on "Collide," the band showed its softer side on its 2006 release, incorporating more strings and vocals by Cooper's wife, keyboardist Korey, while retaining its signature power cords. The group's sound is polished -- sometimes too much so on its studio recordings -- but its catchy rock riffs should play well at a live event.

Also in Skillet's favor: They really, really want to entertain you.

"I look at them as a rock group. The whole Christian, non-Christian thing really had no bearing," said Larry Mazur, a representative from New Jersey-based Entertainment Services Unlimited who booked Skillet for the tour. "They were on a list of bands, and they were just the ones that were the most aggressive to get a slot."

That tenacity has been playing off, said Cooper, who is joined by Korey, drummer Lori Peters and guitarist Ben Kasica on stage. The tour's 20 stops are helping Skillet gain the recognition it will need to match its success in the Christian music industry.

"We are reaching new fans," Cooper said. "People come up after the show and say: 'You guys make me feel good. It wasn't a dark message.'"

Contact Mary Stegmeir at (319) 291-1482 or mary.stegmeir@wcfcourier.com.

{M3Go and do

What:{M3 Skillet opening for Breaking Benjamin, Three Days Grace and Seether

{M3When:{M3 Tuesday, 6:30 p.m.

{M3Where:{M3 McElroy Auditorium

{M3Tickets:{M3 $32.50 in advance; $35 at the door

{M3Call:{M3 (319) 234-7515