The polls in 1997

		By David Cowling Editor, BBC political research

Forty-five voting intention polls were published during the 1997 election campaign.

The election came after more than four years of double digit Labour leads in the opinion polls and those during the campaign did not ruffle Labour's stately progress towards government.

David Cowling: Beware high Labour polls

The only excitement came from an ICM poll published on 27 April which gave Labour only a 5% lead over the Conservatives.

It was the only one during the campaign to give Labour less than a 10% lead.

The final outcome of that election gave the Conservatives a 31% share of the vote across Britain, Labour 44% and the Lib Dems 17%.

How close did the campaign polls come to this actual result?

Labour support over-stated

The polls were reasonably balanced in terms of over- and understating the Conservative vote with 16 polls above and 23 below.

However, they persistently overstated Labour's poll position - 43 polls giving the party ratings above 44% and only two below.

Similarly, Lib Dem support was persistently understated, with only three polls putting them higher than 17% and 38 lower.

Let us take the famous "plus or minus 3%" dictum - the margin of error - and as a crude indicator apply it to each party's rating in every one of the 45 campaign polls.

We find that only two were outside the Conservatives' new range of 28-34%.

However, 34 polls were outside Labour's range of 41-47% - and 19 of these were out by 6% or more.

For the Lib Dems, 20 polls were outside the range of 14-20% and nine of these were out by 6% or more.

History does not always repeat itself, but we should be careful when considering the polls during the current campaign - in both 1992 and 1997 they significantly overstated Labour's final level of support.