Cali & El Dandee target the U.S. after scoring hits in Latin markets.

Scanning through iTunes' top 10 singles lists throughout Latin America and Spain during the past few months, one would invariably come across "Yo Te Esperare" (I'll Wait for You) by Cali & El Dandee, a chart-topper in Argentina, Chile, Colombia and Spain. The track hit No. 1 on radio and sales charts in those countries this summer, and in Spain has been certified double-platinum (80,000) by industry society Promusicae.

The accomplishment is much more noteworthy considering Cali & El Dandee are Colombian, and fewer than a handful of Colombian acts have ever topped Spanish charts. Also, until just four months ago, the duo was completely unknown to the industry. In underground channels, however, Cali & El Dandee have been a sensation for the past year, accruing millions of YouTube views and hundreds of thousands of mentions on social networks. The duo's rapid success illustrates both the importance of online media as a promotional tool and Spanish radio's increasing openness to Latin American music.

Cali & El Dandee are brothers Mauricio and Alejandro Rengifo-24 and 18 years old, respectively-who originally hail from Cali (therefore the name), but now live in Bogota. They started making music four years ago, and Mauricio, a music student at Los Andes University in Bogota, recorded and engineered their tracks, a hybrid of lyrical, romantic pop and rap.

"We just wanted to make good songs and put them online," says Mauricio, who is managed by his longtime friend Pedro Malaver. "Then girls in schools started doing choreography to the music. The songs started playing in Andres Carne de Res [a hip Bogota eatery] and people asked us to play gigs. We played graduations and school parties, and that's where we could see what really worked."

"Yo Te Esperare," in particular, gained traction on Tuenti.com, a Spanish social site for teens. It caught the attention of David Lopez, A&R manager for publishing company Clippers in Spain, who contacted the brothers and signed them to a publishing deal outside of Colombia. At the same time, Warner and Universal Spain started vying for the pair, with Universal signing the act to a three-album licensing deal last spring that includes a share of touring revenue.

Universal Music Spain & Portugal president Fabrice Benoit says he's never signed an act based solely on online traction, but in this case, "we liked every song they put up. Everything worked. They had the hits." The timing was also right. Post-reggaeton, Spanish radio is far more open to Latin rhythms, particularly following the success of DJ Juan Magan.

"Yo Te Esperare" shot to the top of Spain's charts, and Universal quickly released a second single, "No Hay 2 Sino 3," featuring David Bisbal and remixed by RedOne.

"Yo Te Esperare" is No. 4 on Promusicae's Top 50 Downloads list, while "No Hay 2 Sino 3" is No. 11 and was certified gold for 20,000 downloads. On the rise at No. 24 is a new single, "La Playa," featuring Natalia Bauti.

Universal has begun working the duo in Argentina, where "Yo Te Esperare" has been certified platinum by trade group CAPIF for 20,000 downloads, and plans call for a market-to-market rise all the way to the United States.

"Our fans say they like to party, but sometimes it's girls who broke up with their boyfriends and they want to hear something romantic," Mauricio says, explaining why he believes his songs connect with audiences. "Most romantic songs sound the same. But if someone likes Pitbull and wants something romantic with that same vibe and arrangement, they can listen to us."