(CNN) Andrew Yang has launched a write-in campaign for the Ohio Democratic primary in March after failing to fully comply with the state's ballot access laws.

Frank LaRose, the state's secretary of state, said in a statement on Saturday that Yang failed to qualify for the ballot because "petition forms must be submitted complete with a statement from the candidate stating their intention to run." The Yang campaign, "by their own admission," LaRose said, did not do that.

Ohio law requires that candidates soliciting signatures to gain ballot access in the state must do so on so-called "part-petitions" that include a statement from the candidate soliciting the signature, the signatures and a statement from the person who gathered the signatures.

LaRose said that Yang failed to include the first part -- a statement from the candidate soliciting the signatures -- in the majority of their submission.

The mistake means Yang's name will not be on the ballot in a state where 136 pledged delegates -- roughly 7% of the total needed to win the nomination -- will be up for grabs.

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