Garden State helped the Shins escape obscurity; Wincing the Night Away could make them stars.

James Mercer has every reason to be cocky. As the leader and main creative engine of Portland’s the Shins, he’s now officially indie-rock royalty. His band has, to date, moved a combined million units of its first two Sub Pop albums, 2001’s Oh, Inverted World and 2003’s Chutes Too Narrow.

Reflecting its status as one of the most anticipated releases of 2007, the quartet’s latest, Wincing the Night Away, has been given the feature-review treatment by all the music glossies that matter. Critics have praised the group for pushing itself in new directions rather than revisiting the sound that, famously, blew Natalie Portman’s weird little mind in Garden State. Record buyers, meanwhile, have turned the Shins into the biggest players in the indie nation; Wincing the Night Away entered the Billboard charts at No. 2, not bad for a band that’s never been played on mainstream radio.

Yet as cocky as Mercer should be, he couldn’t be more humble and gracious when he calls the Georgia Straight from a tour bus in Milwaukee. Hell, when the conversation eventually winds down, the last thing he says is “Thank you for doing an interview with us.” That’s something you expect to hear from a band that’ll be lucky to draw 20 people to the Pic, not from one that sold out its upcoming Commodore show in 10 seconds. Perhaps the best way to explain Mercer’s lack of pretence is that he can’t believe how insanely lucky he’s been.

“I never really fantasized about being in a band and being successful at it,” the soft-spoken musician says with a laugh. “I never really did that about anything, which was probably sort of an issue for me when I was in college and stuff. I never looked to the future, tried to imagine myself somewhere, and then used that as a target. I don’t know what it is about me, but my head doesn’t work that way.”

He knew exactly where he wanted to go, however, with Wincing the Night Away. After two albums of shimmering, golden-era college rock, Mercer was determined to stretch out on the Shins’ third disc—and first since Garden State turned the group from obscure Portland indie outfit into a legitimate mainstream phenomenon.

“Originally, when we started, my only hope was to get signed,” he says, “to get some sort of recognition to make me feel like this was a legitimate pursuit. That happened. With this record, I knew that this was going to be an incredible opportunity because there were a lot of people out there waiting for it. It’s like I had their ear, so I wanted to both challenge myself and challenge people who had a certain idea about the aesthetic that our first two records shared—the organic quality of the songs.”

There are moments on Wincing where the Shins—which include bassist Marty Crandall, guitarist Dave Hernandez, and drummer Jesse Sandoval—don’t sound that markedly different from the group that recorded Oh, Inverted World and Chutes Too Narrow. Americana-dusted numbers like “Girl Sailor” and “Red Rabbits” make perfect companions to older country dalliances like “Young Pilgrims”. (Mercer’s shitkicker streak is perhaps genetic; his father, a nuclear munitions officer in the American air force, fronted a country band while serving overseas.)

“I always had country music around, so I think it’s only natural that it ended up in what I do,” he says. “It’s a huge part of my musical background.”

Mostly, however, Wincing is a wonderful and weird departure from the Shins that the MySpace generation has come to love. The major reference point this time out isn’t the sound that made indie rock big business in the early ’00s. During his by-all-accounts awkward teenage years, the 36-year-old Mercer spent time in England, where his family was stationed. That put him at ground zero of a post-punk renaissance that produced such seminal acts as the Smiths, the Jesus and Mary Chain, and the Cure. Those legends—which are arguably more influential today than during their prime—would help shape Wincing the Night Away, a record where the drums often sound heavily treated, vocals are echo-laden and multitracked, and guitars occasionally drip MAC eyeliner and Bela Lugosi–black hair dye. Check out the 56 seconds of superfuzzed psycho-candy that is “Pam Berry”, and then marvel at the way “Split Needles” re-creates the brand of dark-garden pop that once made Robert Smith England’s reigning post-punk prophet. Elsewhere, “Sleeping Lessons” starts as a slow-drift space oddity before exploding into a love-and-rockets blast of jangle rock, while “Sea Legs” will charm anyone who hauls out Meat Is Murder on the days when the Paxil just isn’t working.

“I went to high school overseas, and during high school is when you really start to identify with pop music,” Mercer says. “I was surrounded by all these really important bands during that crucial time, and it definitely left a mark on me. It’s strange—I would hate for people to think that the way this record sounds is some sort of pretence or affectation, because it’s really just natural as hell to me.”

From the mouths of, say, the Bravery, that would sound about as believable as George W. Bush’s latest state-of-the-union address. But Mercer comes across as humble enough that you have no reason to doubt him. Hell, he can’t even bring himself to brag about the Shins’ big scene in Garden State, where Natalie Portman insists that Zach Braff listen to the band’s crazily beautiful “New Slang” because it will change his life.

“It was such a great thing for us—that fellow Zach Braff was making a movie, and he showed us a treatment of the scene where they play us,” Mercer notes. “This was early on ­—we knew he wanted to have that song in there. Then, later, we find out that Natalie Portman is going to be in it. It’s funny—that movie wasn’t designed for the mainstream. It was a little indie film that ended up doing well.”

An indie project not designed for the mainstream but that ended up doing well? Funnily, Mercer could easily be talking about the Shins. Except, of course, that he’d never be that cocky.

The Shins play a sold-out Commodore on Monday (February 19).