Despite the fact that Warrington has been Labour-held since the Second World War, the town is remembered more for Roy Jenkins's attempt to win the seat for the infant Social Democratic Party at a 1981 by-election.
His attempt was not quite successful, but he did well enough for the contest to go down in the annals of centre party history. There has never been as close a parliamentary contest in this seat since then.
In 1981 the seat comprised a tiny core of the town, which had long spread far beyond its administrative boundaries. Now the whole of Greater Warrington is included in one borough which is effectively divided into two for parliamentary purposes.
Most of the New Town housing is in Warrington North, which includes the whole of the town north of the Mersey except for the Howley and Whitecross ward which the boundary commissioners transferred to Warrington South prior to the 1997 election.