One Michigan Republican may not make it onto the August ballot.
U.S. Senate candidate Peter Konetchy may not have submitted enough valid signatures.
About 450 of the 15,130 signatures appear to be invalid, that leaves him short of the 15,000 needed to make the ballot.
The Board of State Canvassers will meet Wednesday on Konetchy's candidacy.
Four other Republicans remain in the race against Democratic Debbie Stabenow, Pete Hoekstra, Clark Durant, Gary Glenn and Randall Hekman.