Poll of polls: Tories maintain narrow lead
Updated on 26 April 2010
As the election enters its final full week, the Conservatives maintain their narrow edge over the Liberal Democrats, with Labour third, explains Professor Leighton Vaughan Williams, of Nottingham Business School's Political Forecasting Unit.
There is one new poll out today, by YouGov for the Sun, which puts the Conservatives on 34 per cent, down one from yesterday, the Liberal Democrats on 30 per cent, up two, and Labour on 28 per cent, up one. Fieldwork for this poll was carried out over the weekend.
Polling Commentary
The one opinion poll by YouGov shows the Conservatives slipping a little compared to yesterday's YouGov poll for the Sunday Times, with Labour and the Liberal Democrats up a bit.
The change is within the margin of error, however, and the Political Forecasting Tracker is unchanged, with the Tories on 34 per cent, the Lib Dems on 30 per cent, and Labour on 27 per cent.
Poll of Polls
YouGov/Sun: Conservative 34, Lib Dem 30, Lab 28
Political Forecasting Unit 'polling tracker' has the Conservatives on 34 per cent, the Liberal Democrats on 30 per cent and Labour on 27 per cent, all unchanged since yesterday. The polling tracker is based on recent surveys by different polling organisations, and is adjusted so that the more recent the survey the more weight is attached to the vote shares.
There is also some statistical smoothing which has the effect that outliers or vote shares that diverge most from the general consensus are allocated less weight.
Assuming a uniform national swing, the Conservatives would win 262 seats in the House of Commons, Labour would win 256 seats, and the Liberal Democrats 101 seats.
This would leave the Conservatives 64 short of an overall majority. The markets agree that no one party is likely to win a majority in the House of Commons.
Applying a more sophisticated seats projection methodology, which we term ANS (Adjusted National Swing), which allows for the differential impact of swing on different seats, the Political Forecasting Unit projects the following scenario if the election were held today:
Conservatives: 275 seats
Labour: 234 seats
Liberal Democrat: 106 seats
Others: 35 seats
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Election barometer
The Political Forecasting Unit's 'election barometer', designed to capture the changing state of the race as it unfolds through the campaign, shows the Conservatives on 34 per cent, four points ahead of the Liberal Democrats on 30 per cent, with Labour on 27 per cent.
This is deeply 'hung parliament' territory. On these figures, the Political Forecasting Unit’s ANS (adjusted national swing) methodology projects the following seats distribution: Con: 275 seats, Lab 234 seats, Lib Dem 106 seats.
An analysis of the money placed in political betting markets also suggests that no party will secure a majority of the seats in the House of Commons.
Daily poll of polls
Conservative: 34 per cent
Labour: 30 per cent
Liberal Democrat: 28 per cent
PFU polling tracker (recent polls, weighted)
Conservative: 34 per cent
Liberal Democrat: 30 per cent
Labour: 27 per cent
Outcome: Based on polling tracker, assuming national swing (adjusted) reproduced in every constituency.
Conservatives: 275 seats
Labour: 234 seats
Liberal Democrat: 106 seats
Other: 35 seats
Conservatives short of an overall majority by 51.
Where the money is (analysis based on money wagered on the election in political betting markets)
Conservative: 306 seats
Labour: 224 seats
Liberal Democrat: 86 seats
Other: 34 seats
Conservatives short of an overall majority by 20 seats.
Percentage chances of a majority
Chance of Conservative overall majority: 35.3 per cent
Chance of Labour overall majority: 3.5 per cent
Chance of Liberal Democrat overall majority: 1.2 per cent
Chance of No overall majority: 60.0 per cent
(Chances based on odds from betting exchanges)
Professor Leighton Vaughan Williams is Director of the Political Forecasting Unit at Nottingham Business School.
How the polls have changed
We've taken the data from all our previous Polling Trackers and compiled them into this one graph showing the trend to date. 
