The final opinion polls of the campaign have continued to suggest that Labour will be the largest party in the new parliament, but will probably be short of an overall majority.

Polls conducted late last year and early this placed Labour and its main rival, the SNP, very close together, with Labour usually marginally ahead.

In April, Labour appeared to be drawing away with leads of between 10 and 20 percentage points.

But more recent surveys have shown some reversal of that trend, particularly in the top-up votes, which seem to be much closer.

All polls have had the Conservatives and the Liberal Democrats locked close together in a private contest for third and fourth place.

None of the polls conducted so far has given Labour enough seats to form a government without support from another party.

Possible outcome

The exact outcome is, of course, difficult to predict - and is made more complicated by the use of a new voting system.

However, even if Labour emulates the massive 45.6% of the vote it received during its 1997 general election triumph, it appears unlikely to win the 65 seats it needs for an overall majority.

One key factor in this conclusion is that in 1997 the SNP won only 22.1% of the vote and is polling consistently higher now. The polls have shown far stronger support for the SNP in elections for the Scottish Parliament than for Westminster.

In addition, Labour's 1997 figure must be put in the context of the 42.5% it received at the 1994 Euro-elections and the 39.0% of the 1992 general election.

Opinion polls are generally regarded as having a margin of error of +/- 3%.

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