A year after rocketing to viral fame during the second presidential debate, America’s most famous undecided voter still won’t say who he voted for in the 2016 election.

“You can ask all you want,” Ken Bone told Yahoo News in a recent interview. “I promised I wouldn’t tell anyone, so I’m not going to.”

There’s only one person other than Bone who knows, he said: “That’s my wife — and I don’t think she cares anymore.”

Last October, Bone became an instant internet sensation during a town hall forum in St. Louis, where he came dressed in a bright red sweater and posed an earnest question about balancing environmental interests with U.S. energy needs.

Ken Bone listens to Hillary Clinton during the second presidential debate in St. Louis, Oct. 9, 2016. (Photo: Rick Wilking/Reuters)

“A lot of my friends wanted me to just say something dumb like you would on a morning radio show,” Bone recalled. “But I wasn’t going to throw the chance of a lifetime away for that.”

Instead, Bone’s appearance provided a welcome respite from what had been a nasty debate between Donald Trump and Hillary Clinton.

“It quickly got uncomfortable,” Bone said. “It was like watching mom and dad fight over Thanksgiving dinner.”

Related: 64 hours in October: Yahoo News’ exclusive oral history of Oct. 7-9, 2016

The power plant employee from Belleville, Ill., was selected to participate in the town hall with fellow undecided voters after answering a Gallup phone survey. Bone said he was leaning toward voting for Trump.

“They asked, ‘How likely are you to change your mind, on a scale of one to 10?‘” he explained. “One is, like, there’s no way you’ll change your mind — your candidate could murder a person on television and you’d still vote for them. And 10 was, it’s a total coin flip. And I said, like a two or a three. Like, I’m probably not going to change my mind, but I’m willing to hear what the other side has to say. And based on it being such a polarizing election, a two or a three was considered undecided.”

When Bone arrived at Washington University for a walk-through on the morning of the debate, he was sequestered along with the rest of the town hall participants — for 14 hours.

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Ken Bone waits in the audience to ask a question during the presidential debate in St. Louis, Oct. 9, 2016. (Photo: Jim Bourg/Reuters)

“We didn’t have any electronics, we weren’t watching television — everybody just brought, like, a book to read or something,” Bone said. “Once you’re seen, people start finding out who you are. So if they had let us go again, we almost certainly would have had some rep from a company or someone from a media outlet trying to get us to ask their question instead of ours.”

The sequestering meant that Bone was unaware of the infamous predebate press conference Trump held with Bill Clinton’s accusers, whom the Republican nominee brought with him to the debate.

“The first we heard of that was when he actually trotted them out into the crowd and mentioned them during his introduction,” Bone said. “There was an audible gasp on the stage. Everybody up on the stage, whether they were leaning Trump or leaning Hillary, thought that that was just a tasteless move.”

Ken Bone listens to a question along with Donald Trump and Hillary Clinton during their presidential debate in St. Louis, Oct. 9, 2016. (Photo: Rick Wilking/Reuters)

During the debate, Trump appeared to lurk behind Clinton as she moved around the stage.

“I don’t know that he was trying to intimidate her or do anything weird,” Bone said. “It just seems like that’s how he was playing off his own discomfort or whatever — by pacing around. And he’d always end up somewhere kind of awkward, like way in the back staring at her.”

After it ended, Bone thanked Clinton, who remembered his name.

“She’s like, “Thanks very much, Mr. Bone,” he said.

Hillary Clinton shakes hands with Ken Bone following the second presidential debate in St. Louis, Oct. 9, 2016. (Photo: Saul Loeb/AFP/Getty Images)

Bone, a self-professed broadcast media “nerd,” was taking photos of the TV equipment on the set when he was interrupted by a different Clinton.

“I was taking my pictures, and I heard from behind me, ‘Hey! Hey, you, energy guy! Come here!‘” Bone said. “I turn around, and it’s Bill Clinton, who’s like, he’s pointing at me. ‘Hey! Come here, talk to me for a minute.’ So I walked over, and he tells me how he thought I asked a great question, and coal energy built this country, and we’re going to make sure folks like me don’t get left behind when we have our green energy concerns coming through. I’m like, ‘That’s great, Mr. President, it’s really awesome to meet you.’ And the whole time, his security guy’s tugging on his elbow, like, ‘Mr. President, we gotta go.’”

Also read: Ken Bone continues to charm America after debate

Bone’s 15 minutes of fame, which included appearances on national television shows, was short-lived. A few days after the debate, Reddit users discovered he had made controversial comments on internet forums about the killing of Trayvon Martin and crude remarks about leaked nude photos of the actress Jennifer Lawrence.

Not that Bone, who considers himself a libertarian, was looking to be 2016’s version of “Joe the Plumber,” an undeclared voter from Ohio who made several campaign appearances with 2008 Republican nominee John McCain after a pointed question to then-Sen. Barack Obama at a town hall went viral.

“I refused to endorse anyone at any level,” Bone said. “And both campaigns respected that.”

Pressed again to reveal who he voted for, Bone refused to bite.

“Like I said, I was leaning Trump right after the primaries,” he said. “So I might have still voted for him, or I might have switched to vote for Hillary Clinton, or I might have voted for Gary Johnson. I will tell you I did not vote for Jill Stein.”

— Bone interview conducted by Yahoo News’ Gabby Kaufman

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