The Liberal Democrats' campaign team was quick to move, with Lib Dem candidates openly questioning the honesty of Blair about the legality of the invasion. Charles Kennedy also ended the pact to back Labour candidates in key marginal seats, rubbishing the Labour team's message that voting Lib Dem could hand power to the Conservative Party 'through the back door'.
The Conservatives found it difficult to press home any Labour weakness over Iraq, following their hitherto open support of the invasion. Michael Howard, who has always publicly supported removing Saddam Hussein from power, desperately tried to steer Monday's big Today programme interview with John Humphries back on to domestic policy.
However, Labour's strategy in the last week was to field the Prime Minister for as many big media interviews as possible, clearly deciding he wasn't as much of an electoral 'liability' as first reported.
Having faced a torrid time on the BBC's Question Time special, and damaging headlines over the blame apportioned by the family of a soldier killed in Iraq, Blair remained confidently defiant to the end. But his team now needs to evaluate how much personal credibility Blair has left with the electorate.
This has been a pretty dull campaign in terms of the outcome, but it has challenged previous electoral assumptions. Labour started with a visibly divided leadership and a mistrusted PM. In the face of this Labour fought the best campaign it could.
Trust has been replaced by faith in competence as the main electoral asset, personified by the repeated images of the Blair-Brown partnership.
At HQ it was Alastair Campbell who kept the campaign on track, supported by David Hill whose even temper and good humour was the perfect foil to Campbell's aggression.
Of greater interest now is Labour's next general election campaign, and whether Brown turns to Campbell and other Blairites, or lets his people purge them and their collective campaign experience.
Colin Byrne is CEO, UK and Ireland for Weber Shandwick. He formerly ran the Labour Party press office
This election has had everything. One sacking, a few defections and a sweaty PM on the stocks about war. The only things that have lacked movement are the polls.
From a shaky start, the Lib Dems have run a strong campaign. They have had a lot of luck on the issue of Iraq, but won credit for some policy issues too.
Council tax reform, scrapping of tuition fees and long-term care for older people are now all clearly defined as their issues.
They have also been attacked by Labour, a sign for the Lib Dems that they are now in the big league. A Labour victory with clipped wings is the result most people want.
Were the policies distinctive enough? Was the leadership strong enough?
These are the questions every party asks on the weekend after polling day - this party will be no exception.
Olly Grender, MBE, is a freelancer. She was formerly director of comms for the Liberal Democrats and aide to Paddy Ashdown.
It started as a general election campaign and ended as Britain's biggest by-election. Faced with Labour's seemingly impregnable position, both the Conservatives and Lib Dems sought to turn the contest into a giant protest vote.
'Give Blair a bloody nose' became the underlying message of the two opposition parties as they sought to capitalise on the unpopularity of the Iraq war and a host of other grievances, from tuition fees to tax increases and immigration.
But Blair countered effectively by deploying Gordon Brown at his side to reassure potential Labour defectors.
The predominance of Iraq in the final weeks of the campaign may also have inadvertently damaged the Tory campaign by drowning out potentially more resonant domestic messages.
Nick Wood is MD of Media Intelligence Partners. He was formerly media director for the Tories and chief political correspondent of The Times.