The doorbell rang soon after the start of Tony Blair's Paxman interview. The Prime Minister was being challenged on his role in the death of Dr David Kelly; downstairs, my girlfriend was talking to a local activist from the Liberal Democrats whose presence on the doorstep suggested that he had no interest in this monumental bit of political drama. Reluctantly, I soon left the lounge and joined in the conversation - and within two minutes, I had agreed to help with the Lib Dems' leaflet deliveries and put in a few hours on polling day.
This was not, I am pleased to say, some Damascene, Brian Sedgemore-type conversion to the Orange Way. That became clear pretty quickly when the conversation shifted to my election-related book So Now Who Do We Vote For? - a kind of travelogue-cum-polemic-cum-manual for dismayed Labour voters - and its depiction of Charles Kennedy as a bumbling lightweight. Much to my amazement, the Lib Dem activist seemed to have read it. Slightly less surprisingly, he wasn't best pleased.
"So that was you," he said. His expression slightly darkened. "You weren't very nice about Charles, were you?"
"No," I spluttered. "But I did like Lembit Opik."
That was a little bit disingenuous. What I should have said was something like this: "With the same reservations as thousands of disaffected Labour supporters, I remain committed to the idea that Labour is the best vehicle for progressive politics, and the only party where such quaint notions as equality of outcome and the essential political role of organised labour can still find a receptive audience. I am also of the opinion that right-wing Lib Dems - led by the soft-headed free marketeers who contributed to a notorious volume entitled The Orange Book - have even less in common with people like me than do the Blairites."
But never mind all that. Last year, I moved from Shepherd's Bush to Hay-on-Wye - and round our way, Labour is something of an irrelevance. In the constituency of Brecon and Radnorshire, the Lib Dems beat the Tories by 751 votes in 2001; across the English/Welsh border in Hereford, the margin for their defence spokesman, Paul Keetch, was a no-less nerve-racking 968. To paraphrase a new Labour cliche, to vote Labour in either of those constituencies would have been to increase the chances of waking up with a Tory MP.
What pushed me into temporary Lib Dem activism was reflective of one of the campaign's big stories. Had the Tories come over all metropolitan and non-nasty, I might have been content with simply putting a cross in a Lib Dem box. I can pinpoint the moment at which I first thought I should do a bit more: 15 February, when Michael Howard announced that his latest appeal to voters' more enlightened instincts was based on a policy of screening migrants from outside the EU for HIV and tuberculosis, to show that they would not represent "a danger to public health". His subsequent offensive against travellers, and Enoch-esque agreement with the suggestion that further "uncontrolled" immigration might lead to race riots, made me yet more determined. Whatever I could do to stop the Tory march, I was ecstatically happy to oblige.
My personal election calculations were thus beautifully simple. But, me being a fairly typical dismayed Labourite, the campaign had a slightly more complicated effect on my underlying loyalties. On the morning of 5 May, I was in much the same mood as I had been at the outset of the campaign: convinced, for the sake of Labour's long-term prospects, that some pro-Blair MPs deserved to lose their seats to progressive challengers, and happy to make the case - in line with this magazine's commendably provocative tactical voting guide - for protest voting in safe seats held by government loyalists.
Along the way, however, I had been so pushed and pulled that such certainty occasionally began to fade.
Certainly, if my conversations with other Labour waverers were anything to go by, the shrill pitch of the Conservative campaign inevitably served to assuage at least some of our hostility to the Blairites. This wasn't only a matter of Howard's immigration fixation; when the Tories began their attacks on Blair's integrity, their high-pitched rhetoric inevitably brought out the clannishly contrarian side of the Labour psyche. My mum, a teacher and lifelong Labour member who is as appalled by Blair's flexible attitude to hard fact as Michael Howard affects to be, nailed the effects of his trust offensive as follows: "I can criticise the members of my family, but he can't."
Delivering an even harder nudge back towards the Labour fold, there was one of the campaign's more overlooked U-turns: the sudden snap, early in the campaign, from the government's usual disdain for Labour refuseniks to a sudden sense that they actually wanted us back. Within Labour HQ, the drive for our votes was reportedly given the nickname "Operation Beardy Lefty". The tag didn't exactly suggest a spirit of revived empathy, but its message was clear enough.
At first, however, the old behavioural tics remained. As someone who has had his anxieties about new Labour derided by MPs and ministers as "intellectual" and "self-indulgent" (and even, on one occasion, "obsessive-compulsive"), the sneers sounded boringly familiar - although, in the context of a government supposedly sweating for every vote, they took on a fresh sense of oddness. In early April, I listened to a Today programme item in which John Reid answered the views of anti-war Labour activists in north London with the impatient retort that their concerns about Iraq made them "untypical". A few days later, Peter Hain took the same idea and inflated it into caricature, indulging in the unfailingly hilarious rhetoric whereby the new Labour project is shored up by invoking the class struggle.
Hain said: "There's now a kind of dinner-party critic who quaffs Shiraz or Chardonnay and just sneeringly says, 'You are no different from the Tories'." So what does he drink - lager top?
Within 48 hours, there was a noticeable shift of shtick. "Labour plans to win back voters disaffected by the Iraq war with a manifesto pledge for international action on HIV/Aids treatment, a treaty to control the arms trade and a timetable for phasing out subsidies to the west's farmers," said the Guardian's front-page lead. Meanwhile, the Chancellor had returned from exile, and the idea that Labour might spend the campaign extolling the merits of choice and marketised public services seemed to have been binned.
According to some Labour insiders, in recent weeks rattled MPs had begun reporting back from constituencies that were split between anger and indifference, and they were freshly intent on bringing down the curtain on the "unremittingly new Labour" approach. This was the supposed Doorstep Revolution: not a shot fired, but social democracy allegedly saved.
Just as the accompanying fanfare faded, however, along came the inevitable counterblasts from the ultra-Blairites. There had perhaps been a presentational retreat from the choice agenda, but what did that matter? The manifesto, they pointed out, was sprinkled with precisely the market-based reforms that cause people like me such disquiet. Moreover, their chief proponent was allegedly hell-bent on seeing them through: "The Brownites may not like it, but Blair is still ambitious and eager to serve a full [third] term," ran a headline in the Independent. Elsewhere, a decidedly Blairite post-election reshuffle was rumoured. If such stories suggested that those of us who wanted the Blairites to suffer the odd electoral shock should hold firm, the belated crashing-in of the Iraq issue surely hardened our resolve. For me, the decisive moment came ten minutes into Blair's appearance on that special edition of Question Time (BBC1). Here was the current impossibility of Labour's intended progressive consensus brought to life: no substantive discussion of education, or health, or the environment, or the developing world, given that the Prime Minister was cast yet again as a sweaty Aunt Sally, forced to spend half the programme parrying irate arguments about the war. And the thought came in a flash: the Labour Party - indeed, the entire political system - simply cannot go on like this.
If I had been in a safe seat held by a new Labour zealot, I would have held fast to the idea of protest voting as a means of hastening the restoration of some kind of equilibrium. Moreover, in such tightly contested constituencies as Oldham East and Saddleworth, or Rochdale, or Birmingham Yardley, or Hornsey and Wood Green, I would have voted Liberal Democrat. Though it rather pains me to say so, had I been registered to vote in Bethnal Green and Bow, I may even have buried my misgivings about the Respect coalition and supported the dreaded George Galloway.
To have stuck to that approach when there have been hints of a rapprochement with Labour's alienated supporters might seem slightly counter-intuitive. After all, some of my friends and contacts on Labour's left sound newly chirpy. The party's great debate, they claim, is back on; given time, it may even mushroom into one of the government's beloved Big Conversations. Why not happily succumb to Operation Beardy Lefty and give them the benefit of the doubt?
There are two answers. The first taps into one of the campaign's inescapable themes: given the tangled messages coming from the government's upper ranks and the uncertainty of Blair's departure date, I have my own issues of trust. The second boils down to a matter of elementary strategy. Back in that far-off time when Alan Milburn was reportedly preparing himself to move to 11 Downing Street and the Prime Minister assumed he could cruise to victory as a solo attraction, anti-Blair voting seemed like one last futile bash against a firmly closed door. It having shown signs of creaking open, there has been every reason to keep pushing.
Back on the English/Welsh borders, I ended the election campaign in that corner of politics where the big themes are nowhere to be seen. Trudging through a downpour to deliver Orange leaflets in the sleepy hamlets of Priory Wood, Clifford and Bredwardine, I was doing my bit not for the future of social democracy, but to assist my preferred outcome in a battle at least partly centred on the wisdom of a proposed Hereford bypass, and the unsightly spread of the ad hoc greenhouses favoured by local market gardeners. I didn't mind the rain: my mind was elsewhere: 2009, the Iraq boil lanced, Gordon Brown in his third year as PM, my car parked in a nearby Labour marginal - and the idea that next time, the leaflets might be red ones.
John Harris's book So Now Who Do We Vote For? is published by Faber & Faber (£7.99)