Like the previous year, an established act was selected internally by RTVE. Pop-rock band El Sueño de Morfeo, who competed at the Eurovision Song contest as ESDM, was revealed to represent Spain on 17 December 2012. The song was chosen through a national final.

El Sueño de Morfeo performed three candidate songs in a televised national final that was held on 26 February 2013 at TVE's studios in Sant Cugat del Vallès, Barcelona, hosted by Carolina Ferre.

One of the three finalist songs was chosen through an Internet vote where two songs competed for a spot in the final. The online vote was held from 5 February to 11 February, and users were able to cast one single vote.

In the final, the winning song was selected by a combination of televoting (50%) and jury voting (50%). The professional jury consisted of José María Íñigo (journalist, Spanish commentator for the Eurovision Song Contest), Rosa López (singer, Spanish Eurovision entrant in 2002) and Marco Mengoni (singer, Italian Eurovision entrant in 2013).

On 12 February, the results of the online vote were announced and with 69.9% of the vote, the song "Atrévete" qualified for the final.

As a member of the "Big Five", Spain automatically qualified for a place in the final, to be held on 18 May 2013. In addition to their participation in the final, Spain was assigned to vote in the second semi-final on 16 May 2013.

During the Spanish delegation's press conference on 15 May, Spain was allocated to perform in the first half of the final. In the final, the producers of the show decided that Spain would perform 5th, following Finland and preceding Belgium. In the end, Spain scored 8 points and ranked 25th, second-to-last.

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Wikipedia