I'm told that many close to Nick Clegg reminded him of the old dictum - never apologise, never explain - but he decided that saying sorry was his best hope of persuading voters to listen to the "right things" his party stands for instead of only remembering what he now acknowledges was a mistake.
Speaking at a conference fringe meeting he described Liberal Democrat leader Nick Clegg as a "one nation Conservative" and told the meeting that Mr Clegg referred to him as the "sixth liberal in the cabinet".