BOSTON –- Mitt Romney’s campaign manager admitted regret that the Republican challenger took such a hardline stance on immigration during the GOP primary, one of the first clear acknowledgements by the Romney campaign that its candidate hurt himself among Latino voters.

Matt Rhoades, who oversaw Romney’s campaign, gathered with other top decision makers from both Romney’s and President Barack Obama’s campaigns at Harvard University’s Institute of Politics Thursday for the “Campaign Managers Conference,” which the school has hosted every four years since 1972. The session was on the record, but embargoed until an audio recording was posted online Monday.

During a discussion of the primary, Rhoades and top Romney strategist Stuart Stevens were asked whether they regretted attacking former GOP candidate Texas Gov. Rick Perry on the immigration issue in the summer and fall of 2011.

Stevens, 59, shook his head. But Rhoades, 37, answered the question.

“I regret that …” Rhoades said, before stopping himself, and phrasing his answer differently.

Rhoades went on to describe how the Romney campaign may have regarded Perry as a mortal threat for too long, leading it to engage him beyond the point when it was necessary, and setting itself up for a hard-right turn on immigration.

“If you look through the unwinding of the Perry campaign, a lot of people put a focus on that one infamous debate moment,” Rhoades said, referring to Perry’s epic “oops” moment at an early November debate in Detroit, when Perry could not remember the three federal agencies he planned to eliminate.Read more: