Martina Purdy BBC Northern Ireland political correspondent

Tony Blair had wanted desperately to hold this election in a "positive and constructive" atmosphere.

This, of course, was code for a poll that was pro-powersharing and pro-Agreement.

Instead, the poll is going to be about electing parties for negotiations.

What worries Mr Blair is that this could lead voters to opt for the extremes. When it comes to negotiations, people like to select the hard men.

The pundits in this election will be trying to answer one key question: how will the failure to achieve a resolution with republicans affect David Trimble's fortunes?

Will unionist voters see him as a failed negotiator whose "eye was wiped" by the IRA - because the decommissioning element didn't stack up to his demand for visibility and transparency?

Or will voters have a sneaking regard for David Trimble as the guy who wouldn't dance when the prime minister called the tune?

Will voters see Mr Trimble as the man who bought faulty merchandise - or the guy who got the goods and didn't pay - in effect double crossing republicans?

Now the DUP say they want to negotiate, this is the battle royal in the election - and unionists will have to choose again

Mr Trimble is certain to appeal to pro-Agreement voters to "trust him" to finish the job. Even his own rebel MP David Burnside has said there has been substantial progress on IRA decommissioning.

But in turn, the DUP leadership will present Mr Trimble as a failed negotiator - who can't be trusted.

One of the latest statements from the DUP paints Mr Trimble as weak-kneed, but the Ulster Unionist leader has said he won't take criticism from people who never made it to the negotiating table.

Now the DUP say they want to negotiate, this is the battle royal in the election. And unionists will have to choose again.

'Exposed divisions'

Instead of this election campaign being a re-run of the 1998 referendum in which people were asked to choose whether to accept an agreement, it is more akin to the 1996 Northern Ireland Forum elections when voters chose negotiators.

The UK prime minister has announced that there will be a review held after the poll.

It's hard to quantify what difference a deal may have made to the Ulster Unionist Party's electoral fortunes.

On the downside, pro-Agreement unionists may be confused as to what Mr Trimble is now offering them and stay home

"It would probably have been marginal," said one Irish Government source. Why? Because Mr Trimble would have had to expose his party to an Ulster Unionist Council vote which would have once again highlighted divisions.

The price for decommissioning would have been a source of contention - a pledge to uninterrupted power-sharing, moves on demilitarisation and the highly emotive issue of allowing republicans who are "on-the-run" to come home.

This might have led to Ulster Unionist candidates refusing to sign up to the party manifesto. And as the Labour Party used to demonstrate so aptly, voters don't vote for divided parties. Without a deal, the fractious Ulster Unionist Party will have a veil of cohesion in this poll.

Latest negotiations

On the downside, pro-Agreement unionists may be confused as to what Mr Trimble is now offering them and stay home.

On the nationalist side, a deal was perhaps less important. Sinn Fein wanted to portray themselves as the saviours of the Agreement. Now they will play the wronged victim whose good intentions were spurned.

Sinn Fein will also try to appeal to voters by laying claim to a good relationship with the Ulster Unionist leadership.

Since Sinn Fein and not the SDLP were at the centre of these latest negotiations, there may be a perception in the voter's mind that Gerry Adams is the one who will be cutting the deal post-election.

What is clear is that this election is not going to be a cakewalk for the two parties that dominated the poll in 1998

SDLP leader Mark Durkan - having been left out of the talks because the SDLP wasn't in his words a "problem party" - has a problem.

Mr Durkan will be arguing that Sinn Fein and the Ulster Unionists have failed the Agreement - and hope that SDLP supporters, resentful at their party's exclusion, will be motivated to vote.

Mr Durkan is facing his first election as SDLP leader, and the difficulty for him is that he knows the SDLP was overshadowed in two previous elections - even with big hitters, John Hume and Seamus Mallon at the helm.

Now those big hitters are not even standing.

The last local government poll saw the SDLP over-taken in votes by Sinn Fein. However, because of the proportional representation voting system, the party ended up with a handful more seats. That is what the SDLP will be hoping for.

What is clear is that this election is not going to be a cakewalk for the Ulster Unionists and the SDLP, the two parties that dominated the poll in 1998.

And instead of having a cohesive collective of pro-Agreement parties lined up against the anti-Agreement forces led by the DUP, it's a case of every man - or woman - for himself.