Stephan Savoia/AP Photo

ABC News' Michael Falcone reports:

For months Mitt Romney's campaign has carefully crafted an image of him as a "mischievous," "wild and crazy" and "disobedient" prankster.

On Thursday that portrait came back to haunt him after the Washington Post's Jason Horowitz turned back the clock on Romney, exposing an incident at the private Michigan boarding school he attended during the 1960's when he forcefully clipped the hair of a fellow student who was thought to be gay.

But Romney, his wife, Ann, and even top aides have been methodically piecing together a jig-saw puzzle picture of the former Massachusetts governor that, while never hinting at the kind bullying described by the Post, was clearly meant to portray him as a fun-loving, regular guy.

"Mitt is not what you think at home," Ann Romney said at a campaign event in early December 2011 designed to court women voters in Iowa. "He is my most disobedient child."

She said that her attempts to create an atmosphere of "family decorum," were thwarted by her rowdy husband, who Mrs. Romney said "liked to get them going and get them riled up."

"The five boys - can you imagine at the dinner table - they never behaved," she said, "and Mitt was the worst of all."

More recently, in an interview with ABC's Diane Sawyer, Romney went so far as to say some of the family's dinner table conversations couldn't "be repeated on the air."

"People don't know me terribly well from the - you know, the kinds of pranks we play and what's like in a home with five boys," he told Sawyer. "But most of our dinner table - events were - involving humor of one kind or another most of which can't be repeated on the air."

And last month, top Romney strategist Eric Fehrnstrom told a story about how, as governor Romney "pranked" a state trooper who had intentionally short-sheeted his hotel room bed by penning a fake note saying a hotel maid had been fired.

"The governor showed that to the trooper that had short-sheeted the bed and, of course, his face went white," Fehrnstrom said at a panel discussion organized by the Washington Post. "He was aghast that something like that had happened."

On the campaign trail Romney, himself, has been known to boast about his best pranks like the time he used pink nail polish to scrawl the world "HELP" on the patent leather shoes of a friend on his wedding day.

But Ann has been her husband's most vocal surrogate on the jokester front.

"Stiff, he's not," she said in a recent interview with CBS News. "He's funny."

She added, "I still look at him as the boy I met in high school when he was playing all the jokes and really being crazy, pretty crazy."

In April, the Romney campaign released a web video, featuring a collection of gauzy Romney family photos, in which Ann called Mitt "mischievous and naughty"

"I hate to say it, but often I had more than five sons, I had six sons, and he would be as mischievous and as naughty as the other boys," she said in the video, referencing her husband. "He'd come home and - boom - everything would just explode again.

She noted, "There were a lot of pranks - a lot of pranks."

But the campaign's aggressive effort to showcase the "softer" side of the candidate during his presidential bid has only helped to cement the central anecdote of the more than 3,500-word story, pieced together by the Post. And it has the potential to become as searing as the 2007 Boston Globe story that disclosed how Romney put his family's dog, Seamus, on the roof of a station wagon on a long drive to Canada.

The incident, first reported in the Post, is one that Romney said on Thursday he can't remember. However, he did not dispute it either.

"I don't recall the incident myself but I've seen the reports and not going to argue with that," Romney said in an interview with Fox News' Neil Cavuto. "There's no question that I did some stupid things in high school and obviously if I hurt anyone by virtue of that I would be very sorry for it and apologize for it."