Conyers’ nominating petitions were insufficient, Wayne County Clerk Kathy Garrett said in a statement.
It follows her report last week finding Conyers more than 400 signatures short of 1,000 needed. Garrett said Tuesday that he had 592 valid signatures after challenges.
The 84-year-old Detroit Democrat was at risk because officials believe several people who signed his petitions do not appear to have been registered voters or had registered too late.
Conyers has three days to appeal Garrett’s ruling to the Michigan Secretary of State.