Last January, the Black Keys and Vampire Weekend faced off in a battle royale of modern rock.

The challenge: earn Grammy Award winner Stephen Colbert's vote for best alternative album. "The only way to determine which alternative band has the most edgy, noncommercial appeal is which one got their songs in more commercials," Colbert said on Comedy Central's "The Colbert Report." After the Keys presented three synchs of the same song-2004's "Girl Is on My Mind," featured in ads for Zales, Victoria's Secret and Sony Ericsson-the competition on Colbert's show ended in fisticuffs, crowbars and all. Thankfully, there weren't any injuries, or bruised egos: "We don't ever want to take ourselves too seriously," Black Keys guitarist/vocalist Dan Auerbach says.

"The whole idea of 'selling out' is this archaic indie-rock ideal," Auerbach continues. "They want to give us money to use our music? It boggled my mind why that was a bad thing because to me, my heroes -- blues and hip-hop guys -- take all the money they can get."

The Black Keys' 'El Camino': Track-by-Track Review

Two years ago, after eight years in the business, the Ohio-bred bluesy rock duo started allowing its music to be synched in commercials, TV/film and videogames, ranging from the CW's "Gossip Girl" to Subaru of America. In 2010, the pair was the most-licensed band on Warner Music Group's roster, according to David Bither, senior VP of Nonesuch, the Warner imprint that has been the Keys' home since 2006. The group gets about one synch offer each day, both for new music and older material. Black Keys manager John Peets of Q Prime South, who handles the requests in-office, describes the volume of licensing inquiries as "shocking."

"They write such strong hooks... that's why they've been successful with licensing," Peets says. "Most people think about synchs in terms of complete songs, but really, it's more about which 30-second snippets will work."

Synchs for the Keys' seventh album, "El Camino," released Dec. 6, 2011, include ESPN's Band of the Month (December), Lifetime's "Army Wives" and PlayStation's "MLB 12: The Show" videogame. But synchs are far from the only strategy responsible for breaking the Black Keys in the mainstream.

"Radio, radio, radio," Auerbach says.

It started with a whistled ditty. That was accompanied by start-stop riffs and a retro sheen, courtesy of producer Brian "Danger Mouse" Burton. "Tighten Up" was the final song recorded for 2009's "Brothers," and the album's only collaboration with Burton. It was the band's conscious effort "to make something catchy that could get played on the radio," says drummer Patrick Carney. As a single, "Tighten Up" was a slow burner, but it eventually spent 12 weeks atop Billboard's Rock Songs chart, 10 weeks at No. 1 on the Alternative tally and even cracked the Billboard Hot 100 (No. 87).

The Black Keys -- a band that once toured the United States for seven weeks in a Penske rental truck -- had finally arrived.

But the duo chose not to ride the wave of "Brothers." Three weeks after winning three Grammys (best alternative album, best rock performance and best recording package) at last year's ceremony, the band canceled an Australian tour as well as European dates in order to return to the studio. With Burton now acting as a co-songwriter as well as producer, the Keys spent 40 days at Auerbach's new Easy Eye Studios in Nashville, recording the poppy, punchy "El Camino."

Canceling tour dates "cost us a lot of money because we had to pay for all the venues," Carney says. "We realized we could tour for two straight years, but at the end of the two years we'd have to deal with making a 'comeback record.' We just wanted to make another record. We didn't want to have to prove ourselves again."

Now, "Lonely Boy," the lead single from "El Camino," spends its fifth week at No. 1 on the Alternative chart. (It's thus far peaked at No. 64 on the Hot 100.)

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