'We Are Young': Fun. Tops The Billboard Hot 100 Chart For Fourth Week: Who Are They?

"We Are Young" has topped the Billboard charts for the fourth straight week, and chances are, if you own a radio or a television, then you've heard Fun.'s smash single.

But Fun. is a relative newcomer to the Billboard charts. Formed in New York City in 2008, Fun. was like a new beginning for lead singer Nate Ruess, who had recently broken up with his band The Format. He was joined by Andrew Dost of Anathallo, and Jack Antonoff of Steel Train.

In 2009, Fun. released their debut album Aim and Ignite. It was a quiet release and peaked at No. 71 on the Billboard 200. As of earlier this month, the album had only sold 74,000 copies since its release in 2009.

So it came as quite a surprise when Jeff Bhasker, the hitmaker behind artists like Kanye West, Beyoncé, Alicia Keys and Jay-Z, decided to produce their second album Some Nights.

"We Are Young" was released as the album's first single in 2011. The track featured singer Janelle Monae, enjoyed an early boost thanks to a cover on Fox's "Glee."

However, its use in a Super Bowl commercial for the new Chevrolet Sonic pushed it to the top of the iTunes singles chart. In one week, it jumped 38 spots on the Billboard chart.

"Some Nights" went on to debut at No. 3 on the Billboard 200 albums chart when it was released in February 2012, after selling 70,000 units in its first week, according to Nielsen SoundScan.

Watch: Fun. - "We Are Young":