With just one week to go, and all to play for, the Conservative leader made a savage personal attack on Tony Blair as a man who breaks his promises, and someone with a "whiff of arrogance" about him.
But it was the plea to the electorate to put their trust in him, rather than his party, that marked the change of Tory tactics. In an italicised passage of a text issued in Aberdeen last night, Mr Major said: "I appeal to you. Don't let whatever doubts you may have had about the Conservative Party in the past weigh with you, when the future of the United Kingdom may be at stake.
"Think about it. Think seriously. Think again. look in my eyes and know this. I will always deal fair and true by this great nation."
Mr Major was exploiting the undoubted fact that he is more popular with the voters than his party, fractious and divided as it is. But last night's appeal was also a gamble on the public's willingness to see the election as a presidential contest between two party leaders.
With Labour officials warning of the "nightmare" prospect of a fifth Tory term, and the confirmation of a one-party state, Mr Blair's positive campaign yesterday turned to a new initiative to create a special "People's Lottery" fund, to divert pounds 1bn into popular causes like education and health.
But the Tories last night delivered a diversionary coup by publishing a copy of an old Labour election "War Book" setting out strategic campaign targets. Brian Mawhinney, the Conservative Party Chairman, said the document, sent to the Tories "in a plain brown envelope" six months ago, indicated a campaign based on "smear and scare".
He suggested that the leak could have come from a Labour Party worker who was as appalled by "the cynical attitude of those he was working with as the rest of the country will be when they see this document".
All parties have "War Books', setting out day-by-day campaign strategies, but they normally remain confidential, and Labour said last night that the document that had been sent to the Conservatives was a year old, out of date, and did not include its election masterplan.
The document's summary of Labour weaknesses, it was said, were not Labour assessments, but rather a summary of Conservatives' views.
While Tory campaign strategists are focusing on private polling showing the voters do not trust Mr Blair, Labour campaign managers have noted that the Tories have stopped running their "New Labour, New Danger" poster, with a red-eyed Mr Blair.
They believe that such vicious personal attacks are provoking voter hostility.
Nevertheless, Mr Major last night went for the Labour leader in a strong personal attack, questioning his fitness for office - attacks that will be reinforced in the final days of the campaign.
Contrasting his own leadership style with Mr Blair's, Mr Major said: "Like me or loathe me, on the issues I put before you today you know where I stand."
He accused Mr Blair of having "shifted and shuffled and shifted again" on his plans for a Scottish parliament with tax-raising powers. "I do not truly believe Mr Blair understands Scotland. I wonder sometimes how much he even cares for Scotland. More and more recently he has seemed to care more for the use he can make of Scotland.
"His policy combines a sense of carelessness with a whiff of arrogance that I for one find slightly unappealing ... Mr Blair seems incapable of keeping to one policy for more than a few months."
Ridiculing Mr Blair as "the young mastermind" who said "pass" to questions in the campaign, Mr Major said the Labour leader "in all his experience may not realise that these questions, unanswered, might eventually do our Union to death."
He accused Mr Blair of changing policy to suit his own convenience, and seeking power for its own sake - to win whatever the price. "I see the Labour red is changing to an imperial purple - and I see a man carried away by his own propaganda. How many more promises does Mr Blair have to break before the people of Britain understand his true nature?"
Warning that Mr Blair would "sell out" Britain in Europe, Mr Major said Labour posed three great threats to Britain - more power for the unions, a soft touch for a federal Europe and paving the way for separatism with Scotland. "Labour, led by Mr Blair, will destroy British prosperity, risk dividing Britain and put us on the escalator to a federal Europe."
Labour received a dual boost last night from opinion polls which showed its support holding up, and the announcement that Alan Sugar, the archetypal Thatcherite boss of computer company Amstrad, has switched allegiance to Labour.
Labour is 19 per cent ahead of the Conservatives, according a Gallup poll for ITN's Channel 4 News .Reuse content