(Joe Raedle/Getty Images)

Brett O’Donnell, a former top Bachmann strategist and debate coach, confirmed via e-mail Monday that he is informally assisting Romney’s camp.

“I actually haven’t signed on formally, but I’ve been helping for some time after Michele got out,” O’Donnell wrote. “I am still very focused on helping her move forward as well.”

A Romney spokeswoman also confirmed that O’Donnell is aiding the campaign.

Brett O'Donnell listens to then-Republican presidential candidate Rep. Michele Bachmann (R-Minn.), on Sept. 19, 2011, in Sheffield, Iowa. (Charlie Neibergall/Associated Press)

O’Donnell, who was seen talking with several other Romney advisers at campaign events Monday, is well-known in GOP political circles for working with candidates’ natural abilities, as the Post’s Amy Gardner noted in her September profile of the adviser.

Once a legendary debate coach at Jerry Falwell’s Liberty University, O’Donnell went on to coach George W. Bush in his 2004 re-election bid. In 2008, he played a key role in helping Sen. John McCain (R-Ariz.) prepare for his debates against then-Sen. Barack Obama (D-Ill.).

The O’Donnell news comes as the four remaining GOP contenders — Romney, Rep. Ron Paul (R-Texas), former House speaker Newt Gingrich (R-Ga.) and former senator Rick Santorum (R-Pa.) — prepare to face off at 9 p.m. Monday night for their 17th debate of the primary season.

Staff writer Philip Rucker contributed to this report.