Johnston's manager, Tank Jones, on Monday confirmed a report on Variety magazine's website that Johnston is planning to run for city office in his hometown of Wasilla, Alaska, as part of a reality TV show.
Wasilla is where Palin got her start in politics, moving up from City Council to mayor before winning election as Alaska's governor in 2006.
Jones said Johnston is serious about a run, either for mayor or City Council.
"Let me put it to you like this: If you live in a town and things are happening in that town, and you're displeased with it, what do you do? You try to change those things," Jones said.
He declined to give specifics on what Johnston wants to change but insisted the run is real. "This is not a spoof. This is not a joke," Jones said.
According to the Wasilla city clerk, the next mayoral election is in 2011. The candidate filing period for council elections this October closed July 30. Johnston isn't listed among those candidates.
Wasilla's outspoken current mayor, Verne Rupright, was at a meeting Monday and didn't immediately return a call seeking comment.
Johnston, 20, is the father of Palin's grandson, Tripp, and the recently off-again flame to her daughter Bristol. He has seemingly come to embrace the spotlight since first being thrust into it in 2008, amid Palin's bid for vice president, when he and Bristol were unwed teenagers expecting a child together.
Since then, he's gone on to pose for Playgirl and appear with Kathy Griffin on her reality show. On Sunday, he walked the red carpet at the Teen Choice Awards with singer Brittani Senser, with whom he agreed to shoot a music video.
Asked whether he believed people would take Johnston's run for office seriously, with TV cameras rolling, Jones said: "People questioned Jesus Christ, so I definitely don't care about these mere mortals questioning Levi Johnston.
"People can question whatever they want. I mean, he's going to keep on doing his thing," he said. "He was going to do this, even if this wasn't a reality show."