Bernie Sanders’ presidential campaign plans to ask the Iowa Democratic Party for a recount of the chaotic Iowa caucuses, which melted down earlier this month when a faulty app used by organizers delayed vote tallies.

“Based on what we understand to be the results, we intend to ask for a recount,” Sanders campaign senior adviser Jeff Weaver told the Associated Press Tuesday.

The full results, not released until days after the caucus, showed Sanders narrowly trailing former South Bend, Indiana, Mayor Pete Buttigieg — with Buttigieg capturing 13 delegates to Sanders’ 12.

Weaver told the AP that the campaign will push for a recount after surveying the partial recanvassing the Iowa Democratic Party launched upon Sanders’ request.

The campaign believes the margin of votes to be slim enough that a recount could change the outcome. After Buttigieg and Sanders, Elizabeth Warren placed third with eight delegates, ahead of Joe Biden with six and Amy Klobuchar with one.

Under a recount, the party would have to review the preference cards that caucusgoers filled out on caucus night and rerun all the math in each precinct.