Murray Goot on the impact of federal campaigns

In the past 10 elections, the gap in the level of electoral support for Labor and the Coalition reported by the polls at the start of a campaign, more often than not, has differed significantly from the gap recorded at the election.

The last election was no exception, but there were three - 1996 with Labor in office and 1998 and 2004 with the Coalition - where the gap in early polls proved a good guide to the outcome.

Where campaigns produced significant changes in party support, the pattern was always the same: the lead either narrowed or was reversed. There were no cases of an initial advantage increasing.

via www.smh.com.au