[UPDATE: In a news conference Tuesday, Corbett spoke about how he will file another appeal challenging the decision to keep him off the ballot. See coverage of the press conference and more about the story HERE.]

A major setback has hindered one candidate's chances in the campaign for Iowa governor.

After being challenged on the validity of signatures on his petition to run for the state's top political office, former Cedar Rapids mayor Ron Corbett has lost an appeal, and it appears he will be absent from the ballot in the June 5 primary.

4,005 signatures were needed for Corbett to qualify, and he submitted 4,088, putting him 83 ahead of the requirement. But, The Iowa Republican's Craig Robinson, who acquired copies of Corbett's petitions, called 103 of the signatures into question, saying they were duplicates and not eligible. Such a discrepancy would put Corbett in the hole, at only 3,985 eligible signatures.

CBS2 now reports that a review board has upheld Robinson's challenge and made their ruling by a vote of 2-1, saying Corbett will fall short of the needed signatures and thus, left off the ballot.

We will keep you updated on this breaking and developing story.

[Source: CBS 2, KDATCBS2]