Retired Air Force pilot Jim Ogonowski (R) officially called it quits Friday in his uphill bid against Sen. John Kerry (D-Mass.).

In a blow to national Republicans who recruited him to run for the seat, Ogonowski’s campaign announced on Tuesday that he did not turn in enough signatures to get on the ballot. At that time, he said he was considering all of his options, which would have included either a legal challenge or write-in campaign.

But in a statement released late Friday, Ogonowski took responsibility for the mistakes his campaign made and said that he has no intention of trying to get on the ballot.

“I have made my decision regarding the future of this U.S. Senate race,” he said. “Clearly, we had some issues this week regarding signatures. Mistakes were made along the way. But any good military officer knows that when you are in command, the responsibility is yours alone. The buck stops with me and I take that responsibility.

“There has been and will continue to be a lot of Monday morning quarter-backing and people trying to figure out what happened. But, the truth is, it doesn’t matter. We could play that game all day long. But the facts are the facts. For a variety of reasons, we did not meet the signature requirements. And at this time, I have decided not to pursue this endeavor.

“I provide a sincere thank you to those that stood by me. I am sorry that we did not succeed. I ask for patience as my family and I move forward.”

Ogonowski’s folksy charm and unique story caught the eye of Washington, D.C., political operatives when he held Rep. Niki Tsongas (D-Mass.) to a 6-point win in the 5th district special election in October.

The 5th district race was considered a long shot, but the Senate contest would have been an even more difficult campaign given Kerry’s stature in the state and his $9.2 million in the bank.

The 10th district GOP nominee from 2006, little-known Jeff Beatty, remains on the ballot to take on Kerry this fall. Massachusetts has not sent a Republican to Congress in over a decade.