Clad in a tight-fitting white dress with a cut below the neckline to show much of her cleavage, Julia Orayen was working as an assistant on the televised debate, which focused on the economy and the drug-related violence ravaging Mexico.

At the start of Sunday night's debate, Orayen walked in front of the camera to hand out cards to the four candidates, and created an immediate stir on online social media.

The appearance lasting a few seconds quickly began trending on Twitter, generating thousands of mentions. Mexican newspaper Excelsior declared her the online winner of the debate.

While many Mexicans celebrated Orayen, others condemned the Federal Electoral Institute (IFE) for the incident, saying it had undermined the seriousness of the debate.

The IFE later issued a statement apologizing to the citizens of Mexico and the candidates for the "production error associated with the dress of an assistant."

A Twitter account in Orayen's name has picked up more than 7,000 followers since the two-hour debate.

Orayen posed nude for the Mexican edition of Playboy in 2008, a spokesman for the magazine said.

(Reporting by Lorne Matalon; Editing by Sandra Maler)

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