When you listen to Rilo Kiley’s newest album, More Adventurous, it becomes readily apparent why magazines like Rolling Stone call singer Jenny Lewis things like “indie rock heartthrob of the year.”

Lewis sounds like Patsy Cline with a lip ring – a heartbroken, city-smart girl who is attracted to everything that’s bad for her. Her voice sprawls all across the new album like hair on a pillow. Whether she’s belting out a country torch song, a folk ballad or a pop-rocker like single “Portions For Foxes,” Lewis is always running the show. She can coo teasingly or tear into you like an animal. Either way, she comes across cute as a button.

As it turns out, Lewis has had plenty of practice being a cute, little heartbreaker. A former child actor, she spent her formative years making puppy love on just about every ’80s sitcom you can remember. (For example, she was Ben’s first kiss on “Growing Pains.” Remember that one?)

There’s something about Lewis’ singing that almost makes you feel like you miss her, even though you’ve never met. See how creepy that last statement sounded? That’s the effect she has on hundreds of thousands of emo boys all across the country. They’re all in love with the red-headed girl they saw on MTV. Just imagine what that’s like from her perspective.

“I think it kind of freaks her out,” says drummer Jason Boesel from his home in L.A. “It’s starting to be like she can’t really hang out after the show. It used to be, she would go sell our merch. But now she can’t really come out. So yeah, it can get out of hand a little bit.”

The good and/or bad news, depending on how you look at it, is that it’s about to get a whole lot worse. When we spoke, Boesel, Lewis and the rest of Rilo Kiley were preparing to head out on the road as the opener for Coldplay on what is one of the biggest and most high-profile stadium tours of the year. If things were getting crazy for Rilo Kiley before the tour, they’ll soon be absolutely b-a-n-a-n-a-s.

For the time being, Boesel is doing everything within his power to distract himself from the fact that he’ll soon be sharing the stage with one of the biggest bands in all of rock and roll.

“I think it would be unwise to think about it too much. You can psyche yourself out. I think we’re just treating it like any tour, and we’ll see what happens,” he figures, adding with a chuckle, “I have a feeling that once we show up for soundcheck on the first day, we might feel different.”

Needless to say, success on this scale is a rather new experience for Rilo Kiley. Although it calls L.A. home, the group first developed a buzz while on the roster of Omaha-based label Saddle Creek, home to indie luminaries like Bright Eyes, Cursive and The Faint. There, the band gained enough indie rock credibility to last a lifetime, while the songwriting team of Lewis and guitarist Blake Sennett (Lewis’ ex-boyfriend, who also happens to be a former child actor) blossomed into something formidable. Their twinkling brand of indie-rock country-pop became increasingly catchy and increasingly accessible to music fans outside of the indie rock realm.

“If you play music with the same people for a while, I think you naturally want to refine it. So that tends to lead to a poppier sound, because pop music often is not only refined, but overly refined. So I think we try to ride the edge to make produced music that doesn’t sound overly cheesy,” Boesel says. “I think Jenny does a great job with adding a darkness, even to the poppiest songs, with her lyrical point of view. So I think she gives us a lot of leeway musically to play with.”

But no matter how much they toy around with pop melodies, bands on obscure labels based in places like Omaha, Nebraska, usually don’t end up playing Madison Square Garden with bands like Coldplay. And Madison Square Garden with Coldplay was exactly where Rilo Kiley wanted to be. And so, when it came time to release More Adventurous, the band split from the indie collective and started its own label, with distribution by Warner Bros.

The move was actually rather risky. On one hand, Rilo Kiley was in danger of alienating its core fanbase of indie rock kids. On the other hand, there was no guarantee whatsoever that the band would survive in the mainstream realm.

And so, somewhat naively, and with all of its eggs piled high into one basket, Rilo Kiley entered the major label arena.

“I think that as a band we are kind of all – I wouldn’t say impatient – but we are all striving for the next thing,” Boesel explains. “We wanted to take a chance and grow our band as much as we could within the limitations of the music we make. I don’t think we wanted to change our music too much, but we saw an opportunity, and I think we would have regretted it had we not taken it.”

A year later, having played some of America’s biggest festivals (Coachella and Bonnaroo) alongside the world’s biggest bands and landed on just about everyone’s “best albums of the year” list, Rilo Kiley is breathing a little easier.

“There have been bumps in the road,” Boesel concedes, “but any path you decide on will have its obstacles. So I think we were all satisfied with what we did. It was the right choice, and it actually did what we wanted it to do. And it’s not even over yet.”