Conservative support reflected voters' perceptions of the economy, not parliamentary politics, David Sanders, Professor of Government at Essex University, said.
'You would be hard-pressed to show any effect from the Government's defeat in the Commons on opinion outside Westminster,' he said. 'If the Government had not won its vote of confidence, then clearly there would have been some sort of effect. But the influence on opinion of even big events dissipates fairly quickly.'
Research at Essex has scanned opinion poll and other data during the past 15 years for any trace in voting intentions of fall-out from compelling political events at Westminster. 'I have even examined the data to see whether Spitting Image had any effect on perceptions of particular characters at particular times. It didn't,' Professor Sanders said.
'The really big events - the Falklands war, the miners' strike, the Gulf war - do change opinion, though the effect of the Falklands war was not as big as some people think. Economic perceptions are what matter crucially.'
The most recent poll, published on 9 July, revealed that an increasing proportion of those polled anticipated deterioration in the financial situation of their household.
Gallup, for the Daily Telegraph, found 35.5 per cent expected their fortunes to get a little or a lot worse during the next 12 months, a perception held at the 1992 general election by only 16.3 per cent.
More than one in three Conservative voters was dissatisfied with Mr Major as Prime Minister.
The polls, which failed to predict a Conservative victory at the general election, estimate that more than 40 per cent of the electorate would now vote Labour, with the Liberal Democrats overtaking the Tories. At the general election, the Conservatives won 42.8 per cent of the votes, Labour 35.2 per cent, Liberal Democrats 18.3 per cent, and other parties, 3.7 per cent.