U.S. Senate hopeful Roy Moore has a new challenger – a retired Marine colonel.

With just 13 days until the Alabama special election, Col. Lee Busby has entered the tight and bitter race to fill the seat once held by U.S. Attorney General Jeff Sessions. Busby is running as an independent write-in candidate against Moore, the Republican dogged by sexual misconduct allegations, and Democratic nominee Doug Jones.

“It all started out with me walking down the street thinking: ‘Hell, I’d vote for me before I’d vote for either of those two guys,’” Busby told Fox News.

He said his decision has nothing to do with the handful of women who claim Moore sexually harassed them when they were underage.

“I have no idea what’s at the foundation of all of that controversy,” he said. “It’s not my issue, on a personal level.”

Multiple Republicans have called for Moore’s removal, including Senate Majority Leader Mitch McConnell and Sen. John McCain.

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Sexual allegations aside, the colonel said he’s always had a gripe with Moore.

“I don’t think his professional qualifications speak to the U.S. Senate,” he said. “He’s a judge, that’s great.”

As for Jones, Busby believes that he fails to represent Alabama voters.

The retired colonel believes his candidacy gives Alabamians a more reliable option, and his lengthy resume proves his qualifications for the job. He served for 31 years in the United States Marine Corps, half of which were spent in active duty. He served in Iraq for about a year in 2007.

He served as deputy chief of staff for Marine Forces Europe and also served as vice chief of staff for Lt. Gen. John Kelly, the current White House chief of staff for President Trump, at the Marine Forces Reserve.

He said it was a privilege to work for Kelly, but he insists his campaign has nothing to do with his former boss’ position in the White House.

“I think you tend to work easier with people you know and trust,” Busby said about Kelly, adding that “this is not based on that.”

Busby said he offers more than military experience.

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As an investment banker, entrepreneur, small-business owner, and employee of a multinational corporation, Busby said he possesses the skills and knowledge to become much more than a military leader.

“It’s actually much more varied than that,” Busby said about his career. “And I think that’s a strength.”

The write-in candidate says he’s never before considered running for political office, but believes this long-shot campaign was “custom made for him.”

“I would never, ever make it in a conventional campaign,” he said. “I’ve never been interested or willing to pay the kind of political dues that one has to pay to move up.”

Even with the controversy surrounding the race, the little-known write-in candidate is a very-long shot contender -- for Alabama voters to elect him, they must write in “Lee Busby” on their ballots.

The bigger question is not whether he'll win, but how his candidacy might tilt the race by drawing votes from Moore or Jones.

Although some have questioned his intentions, particularly since he entered the campaign so late, he says his motives “come from the heart.”

As for his policies, the newcomer plans to support the Republican platform, including repealing and replacing ObamaCare, supporting the tax reform bill, pushing for stiffer immigration laws and supporting a pro-life agenda.

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“I’m a centrist candidate, Republican voter, and supporter of the Republican agenda in the U.S. Senate,” Busby wrote on his official campaign page.