The Wisdom of the Crowds #4

There is something worrying me, which I would like reassurance about.

Luke Akehurst wrote today that "the Tories are not going to get anywhere near winning if they can only manage a 3% lead at this stage in the electoral cycle (despite shiny new leader). Cameron is 11 months into his leadership. When Blair had been leader of the opposition for 11 months he was 19% ahead," echoing received wisdom that British governments tend to do worse in mid term polling and then do better closer to an election. But this doesn't appear to be true.

I had a quick look at opinion polls from ICM and MORI, and compared the polls eighteen months after the last election to the next election result (i.e. the situation we are now in). In every case bar one, what happened was that the Tories increased their support as an election got closer, and Labour did worse. This was the case irrespective of which party was in power.

In November 1980, Labour were 14% ahead, and lost the next election by 16%
In December 1984 Labour were 4% behind according to Mori and 9% according to ICM, and lost the next election by 11%
In December 1988 Labour were behind by 10% (Mori) and 6% (ICM), and lost the next election by 8%
In October 1993 Labour were ahead by 16% (Mori) and 3% (ICM), and won the next election by 13%
In November 1998 Labour were ahead by 24% and 22% and won the next election by 9%
In December 2002 Labour were ahead by 14% in both polls and won the next election by 3%