ELECTION '05: Labour is heading for General Election victory, according to the results of opinion polls published yesterday.

But the surveys offer widely different estimates of the extent of its lead, as the parties square up for the first week of full-scale campaigning and the publication of their manifestos over the next few days.

A Mori poll for The Observer and Sunday Mirror put Tony Blair's party a hefty seven points ahead among those certain to vote, with 40 per cent, against the Conservatives' 33 per cent and the Liberal Democrats' 19 per cent.

Labour's lead was a more modest four points in an ICM poll for the Sunday Telegraph, with 38 per cent, against 34 per cent for the Tories and 20 per cent for Charles Kennedy's party.

But a YouGov survey in the Sunday Times gives Labour a far slimmer lead of only two points, putting Mr Blair's party at 37 per cent, against Michael Howard's on 35 per cent and the Lib Dems on 21 per cent.