Labour has reaped considerable advantage over the years from the operation of first past the post in Scotland. Perhaps surprisingly, the party has never polled 50% of the vote (the Conservatives did manage to do so in 1955), but has regularly taken more than half the seats. In 1997 a 45% share of the vote yielded three quarters of the total seats.

The Conservatives, by contrast, have seen their decline in support in Scotland exaggerated by the operation of the electoral system. The Liberal Democrats in Scotland have tended to receive a 'fair' return for a modest national vote thanks to the concentration of their support in rural areas, while the SNP have suffered from having a more even spread of support.

Scotland forms a single region for the European Parliament elections, meaning that votes across the country will be totalled before the 8 seats are allocated. The electionis being held five weeks after the Scottish Parliament contests and what happened then will have an important impact on these results.