AFTER two successive election victories, a hat-trick looks a certainty for a buoyant prime minister. Throughout the campaign, the polls point to another convincing majority for Labour. But the electorate has a surprise up its sleeve, and decides instead to deliver the keys to 10 Downing Street to the Tories.

The memory of Harold Wilson's shock defeat in 1970 is the spectre haunting Labour strategists. Despite the strength of the economy and in the face of all the poll evidence, Ted Heath's victory is a reminder that nothing can be taken for granted.

And it's a vision that is proving useful to Tony Blair. With a low turn-out seemingly the major obstacle to another Labour victory, the prospect of a Conservative government led by Michael Howard is the most effective way of getting his supporters to vote.

But whether it's a genuine fear or a convenient scare tactic, the waiting will soon be over. With just one full day of campaigning remaining, tomorrow the nation - or at least the 60 per cent of it which bothers to vote - goes to the polls to give its verdict.

It may be the most competitive election since 1992, but it has largely failed to ignite the popular imagination. This year there has been no War of Jennifer's Ear, no memorable election broadcasts, so soapbox - not even John Prescott lamping someone. Yet.

"Other than Iraq, there are no serious concerns in society as a whole to make people go out and be engaged with politics," says Martin Farr, history lecturer at Newcastle University. "It is very easy for people to become apathetic/contented.

"They're not necessarily supportive of the people in power, but they're not sufficiently annoyed or critical to go out and change things."

The lack of deep divisions - at least between the programmes if not the philosophies of the major parties - is reflected in a negative and highly personal campaign, which finds its apogee in Iraq. While Iraq may not figure highly on voters' lists of priorities, it is a prism through which the whole campaign can be seen, and for Mr Blair's opponents, it symbolises all that is wrong with the Prime Minister.

But if the Tories do not win the election, at least they can have the consolation of winning the campaign.

"It reminds me very much of the 1987 campaign, when the opposition has the best campaign," says Dr Farr. "This time, the Conservatives have run a much tighter ship."

He points to the way the Tories have largely dictated the agenda, particularly in the first two weeks of the campaign, recovering from the disaster of the very messy sacking of Howard Flight. Asylum and immigration and cleanliness in hospitals all had Labour on the back foot early on, and the Conservative campaign has generally run smoothly and been well-organised.

"This election is as much about what you don't want as what you do want," adds Dr Farr.

Turn-out is expected to be one of the keys to the election. After reaching a low of 59 per cent four years ago, it is tipped to rise this year, partly as a result of more widespread postal voting. The weather could also play a role: a sunny day means more people vote, and a higher turn-out is widely considered an advantage for Labour, whose supporters are generally less inclined to vote than Tories.

Nick Randall, politics lecturer at Newcastle University, puts the Liberal Democrats as the campaign winners, overcoming their own shaky start in the form of Charles Kennedy's apparent lack of grasp of his party's tax policy. But he too points to the Tories putting their agenda forward more effectively than Labour during the last three weeks.

"Labour, despite its 13,000 word manifesto, doesn't seem to have put forward much in the way of campaign themes," he says. "Their main campaigning point is the economy, but there is not much of what is going to happen in the next four or five years."

But he warns that negative campaigning and personal attacks could increase voter alienation from politics and lower turn-out.

"A lot of people switch off and start thinking that all politicians are the same, nothing is going to change and there is no point going out to vote," he adds.

Dr Randall forecasts a Labour majority of 60-70 seats. "The argument that the Conservatives have got too much to do is valid," he says. "They're going to need a huge swing and, going on the polls, they are nowhere near."

Under 200 seats will spell disaster for the Tories, and almost certainly for Michael Howard's leadership too. With his age - 64 in July - against him, the pressure on him to go will be almost irresistible.

"Probably the sensible thing for the Conservatives would be to keep him for 12-18 months and stabilise the ship," says Dr Randall. "The problem in 1997 and 2001 was there was a leadership battle before the MPs got back to Westminster.

"There is also a problem in that there are not many notable Tories coming through and even for political anoraks it is a struggle to remember the front bench."

But perhaps the most significant development of the campaign concerns the relationship between Tony Blair and Gordon Brown. Just a few months ago, there was talk of the Chancellor being moved after the election, perhaps to be sidelined at the Foreign Office. Darlington MP Alan Milburn was in charge of the campaign, giving him valuable ballast when the time comes for a leadership election to succeed Mr Blair.

Now, all talk of sidelining Mr Brown has been brushed aside. With polls showing voters preferring him to Mr Blair as prime minister, the Chancellor became indispensable to Labour. The result was Mr Blair confirmed his rival would continue as Chancellor if Labour wins.

Perhaps more importantly, at times it seems Labour's campaign has been run as a double act, the Prime Minister appearing alongside his Chancellor whenever possible, and the Chancellor called in to protect his beleaguered Downing Street neighbour. Poor Mr Milburn seems to be the one who has been sidelined.

"It has strengthened Brown's position enormously," says Dr Randall. "If Labour do get back in, it won't necessarily be seen as Tony Blair's victory, as it was in 1997 and 2001. The Chancellor has shown himself to be significant to the electoral appeal of the party."

This dual presidency has also made it more likely that, whatever the Labour majority, Mr Blair will not serve a full term, and when he does step down the succession will be fairly straightforward for Mr Brown.

"Because the Prime Minister has declared his intention to retire, whenever there is any difficulty within the party and the government, people are going to be whispering that maybe it is time for him to go," says Dr Randall.

"It is going to be difficult for him to pull off a full term, if that is genuinely what he wants. He will have to hang on by his political fingertips."

He says the likelihood is that Mr Blair will retire after 18 months to two years of the new parliament, giving his successor at least two years to develop their own style of government before the next general election.

The next election may also see the Tories in a position of needing just one more heave to regain power, depending on what happens tomorrow, says Dr Farr, who is predicting a Labour majority of 70-80 seats. "There are judders that quite a few seats could be lost because a few thousand Labour supporters stay at home," he says.

"That will probably hasten Blair's departure, and the question then will be whether Brown can sufficiently revitalise the party, because the next election will be even tighter."