Was just reading the Wiki entries you so thoughtfully provided harleywoman. Still don't have any idea on how the competition works, but this paragraph got my attention:

El Monstruo
Traditionally, the audience attending the Quinta Vergara for a Festival each year openly demonstrates its acceptance or displeasure on the acts that perform there, be they contestants in the two competitions or established artists. As a result, Chilean media has nicknamed audiences at the Festival as "El Monstruo" ("The Monster"). Earning acceptance from "El Monstruo" usually has a direct impact on an artist's popularity -particularly that of Spanish language pop stars- on the rest of Latin America. Conversely, booing artists offstage is not uncommon.

Artist compete in the Festival's regular competitions for one of three awards: "Gaviota de Plata" (Silver Seagull), "Antorcha de Plata" (Silver Torch) or "Antorcha de Oro" (Golden Torch). However, audience response from the "Monster" may demand that one of the three awards -or, progressively, all three- also be granted to an established act as their performance progresses. An artist that "tames The Monster" by earning all three awards receives recognition as a major star by Chilean and Latin American media almost immediately after a successful performance.

All I can say is that I hope he gets to sing something other than Rock Around the Clock. Don't get me wrong, he did a good job with it, but it doesn't showcase how beautiful his voice is. Wonder if they have to do covers or if they can use their own songs. I bet Elliott's a whole lot less nervous about this than he was for Idol.

Best of luck Elliott.