Now, Conyers will have to run as a write-in candidate in the primary.
Conyers submitted 2,000 signatures in April, but two of the gatherers were found to not be registered to vote, a legal requirement for people who collect signatures in Michigan. That put Conyers under the minimum number of signatures needed to get on the ballot.
The American Civil Liberties Union has challenged the law that requires signature collectors to be registered voters and the Conyers campaign is preparing its own legal challenge.
Conyers' campaign chairman, state Sen. Bert Johnson (D-MI), said to the Detroit News on Monday that the congressman would prepare a legal challenge as well as make preparations for a write-in campaign.