From ESPN:

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Almost 700 fans submitted video testimonials explaining why they should represent their team, according to ESPN.

“The four chosen will have their fandom on full display – 45 feet in the air on a 40-foot wide by 8-foot deep billboard,” said ESPN in a press release. “Throughout their time on the billboard, the fans will participate in activities and challenges to earn cash and prizes, many of which will be based upon fan engagement on social media. After the semifinal matchups, the two fans whose schools faced defeat will depart, and the two finalists will remain on the billboard until Jan. 7. Their devotion will be rewarded with prizes and the opportunity to support their team at the National Championship game, not to mention being named their team’s most adventurous and dedicated fan.”

The four fans will take their position on the billboard on December 27th and the stunt will be livesteamed on ESPN3.