Michigan’s elections bureau said late Monday that five Republican candidates for governor, including two leading contenders, failed to file enough valid nominating signatures and should not qualify for the August primary.

The stunning recommendations immediately transformed the race in the battleground state and dealt a major blow to former Detroit Police Chief James Craig, who has led in primary polling despite campaign problems, and businessman Perry Johnson, who has spent millions of his own money to run. Democrats had challenged their petitions, alleging mass forgery and other issues. Another GOP candidate, Tudor Dixon, had also contested Craig’s voter signatures as fake.

The bipartisan, four-member Board of State Canvassers will meet Thursday to consider the elections bureau’s findings of fraud across five gubernatorial campaigns. The Republican candidates, who are vying to face Democratic Gov. Gretchen Whitmer in November, could end up going to court if they do not make the ballot.