DENVER |  Republican U.S. Senate hopeful Jon Keyser on Tuesday challenged his disqualification from Colorado’s GOP primary, seeking a court order that would put his name on the June ballot.

The former state representative and one-time favorite to challenge Democratic Sen. Michael Bennet argued that Secretary of State Wayne Williams erroneously rejected voter signatures that Keyser needed to make the primary.

Denver District Court Judge Elizabeth Starrs said after a hearing she would have a ruling by Friday.

Keyser needed 1,500 signatures from registered Republican voters in each of Colorado’s seven congressional districts to qualify. Williams found that Keyser fell 86 signatures short in the 3rd Congressional District, which is represented by GOP Rep. Scott Tipton.

Keyser argued in a court filing that Williams mistakenly rejected 186 valid signatures from that district. Williams said Monday that the person who collected those signatures isn’t a registered Republican, as required by law. Keyser insists that person is a registered party member and that the 186 signatures should be accepted.

Keyser, an Air Force reserve officer who served in both Iraq and Afghanistan, chose to petition his way to the primary rather than earn a spot at the state Republican assembly earlier this month. El Paso County Commissioner Darryl Glenn advanced to the primary at the convention.

Jack Graham, a former Colorado State University athletic director, has petitioned his way to the ballot. Businessman Robert Blaha and former Aurora city councilman Ryan Frazier await word on their own petitions.

Keyser and his attorneys maintain that he submitted the required 1,500 petition signatures from each of Colorado’s seven congressional districts, which was required for Senate candidates to make it onto the June 28 Republican primary ballot. On Monday, the Secretary of State’s Office announced that Keyser was 86 signatures short of the 1,500-signature threshold in the 3rd Congressional District, which encompasses the majority of the Western Slope.

In a court filing provided by Secretary of State spokeswoman Lynn Bartels, attorneys for Keyser claim that one of the candidate’s petition gatherers in the 3rd Congressional District, Tyler Gonzalez, had his signatures unfairly disqualified from the overall tally.

Gonzalez collected a total of approximately 429 signatures, nearly half of which were from the 3rd Congressional District — for the Keyser campaign in February and March, according to an affidavit signed by Gonzalez. However, a court filing claims that because Gonzalez failed to change his address when he officially registered as a Republican last year, the Secretary of State’s Office was unable to confirm if he was in fact a registered Republican, disqualifying his collected signatures. Under state law, petitioners must be affiliated with the political party of their respective candidate.

Gonzalez had collected a total of 186 valid signatures from CD3, according to the court filing. His affidavit was signed and notarized by Ryley Johnson and Jason Cogzell, who supervised Gonzalez during the signature-gathering process, according to the affidavit.

The Keyser campaign believes that the Secretary of State’s office unfairly rejected petition signatures collected by other petitioners as well, according to the court filing.

“The Keyser campaign continues to evaluate the signatures rejected by the Secretary in the 3rd Congressional District,” according to the document. “On information and belief, there were many other signatures wrongfully rejected in this congressional district.”

Keyser’s ejection from the Senate race would leave four potential candidates: El Paso County Commissioner Darryl Glenn, former Colorado State University athletic director Jack Graham, Colorado Springs businessman Robert Blaha, and former Aurora city councilman Ryan Frazier.

The Secretary of State’s office is still counting petition signatures for both Frazier and Blaha.

The Associated Press contributed to this story.