Sir Menzies Campbell: Spot the old man out

The Lib Dems refused to go into a general election with a leader pushing 70 – yet that's when many men are just hitting their stride

Sir Menzies Campbell was in fine form as he spent an unusual evening among friends and allies. A leader at odds with many in his 21st-century party positively shone days ago in the town he declared "a crucible of 19th-century liberal thought".

At a convivial annual dinner with Rochdale's all-conquering Liberal Democrats, he let his audience in on the "three key principles ... at the heart of my bid for government". Few of the 150 Lib Dems gathered in the historic town hall to hear their special guest's "sparkling" address suspected he would be gone so long before polling day.

"He gave no indication at all," said Rochdale MP Paul Rowen. "Indeed, he was very upbeat and revelled in the success of the party ... and looked forward to the future."

It is unlikely that even the perennially embattled Sir Menzies Campbell believed his own future as leader would not stretch into the middle of the following week. But less than three days after he took his bow before Rochdale's Lib Dems, he had left them bemused and searching for a new leader.

It is somewhat ironic that Ming decided to give up as the prospect of an early election disappeared. It could have signalled an end to the panic at Lib Dem HQ over the imminent danger of being squeezed to a rump by a resurgent Tory party. Instead, as one Campbell loyalist explained: "If the party had been anxious about fighting an early election behind a man in his mid-60s, it was terrified by the prospect of being led into the next one by someone pushing 70."

Ming had appeared to weather the persistent criticism of his age and leadership qualities that had provided the subtext to the party conference when he told a regional party gathering in Suffolk, the day after his triumph in Rochdale, that talk of a leadership challenge was "idle chatter".

In reality, however, he had already begun to broach the leadership issue in one-to-one meetings with trusted colleagues, and had not received the level of enthusiastic support he had craved. It was his friends, and not his enemies, who delivered the fatal blows.

Ming had been disappointed by the wider response to his speech on Saturday – the mood darkened by the public admission on the part of the party president, Simon Hughes, that the leader "has to do better". But when Ming boarded the train from Edinburgh to London on Monday morning he was fully prepared for another week at the coalface of the party leadership. Barely had he arrived at his desk in Westminster, however, than he decided to resign.

Allies point to the continuing poor coverage as a key factor. "He found the usual digest of negative press cuttings waiting for him and decided he would never be able to turn it round," one said. But they also admit that the media's obsession with his age was not a sufficient reason to give up. The truth is that the rumblings of discontent were beginning to coagulate into a movement against him, with supporters of the most likely successors briefing about the need for change.

During a meeting with his media manager, Mark Webster, and Archy Kirkwood, his long-term ally and chief of staff, the leader gave in to the inevitable. Discreet polling of grass-roots voices, MPs and, crucially, Lord Kirkwood's own conversations with party grandees including Lord Ashdown, confirmed profound doubts about his ability to carry on.

"I think he realised that another two or three weeks of the continuous back-biting would have led to him being forced out in ignominy," a veteran Lib Dem MP said. "He didn't want to have junior MPs telling him he had to go. So he said 'Fuck it, I'm going on my terms – I won't be humiliated like Charles Kennedy was'."

As the news filtered out, Ming rang his wife Elspeth to tell her that he had resigned, and would be home for supper. They would watch the fall-out from his bombshell from the comfort of their sitting room. He had returned to life as a normal 66-year-old.