Traditionally the first-past-the-post system was endorsed as keeping extremist parties at bay by manufacturing a parliamentary majority for the party that won a plurality of the popular vote. Last July, for example, the Labour Party won more than 63 percent of MPs with barely a third of the popular vote, while the Reform Party gained less than 1 percent of seats with fifteen percent of the popular vote.
Polls in January showed that the FPTP system was still working as expected. However, this month's polls show that Reform is now a winner from the FPTP system. Besides coming first with 26 percent of opinion poll support, it is predicted to come first in the Commons with thirty percent of MPs. Given that predictions are only statements of probabilities, on current figures there is a 7 percent chance that Nigel Farage's Reform Party could win an absolute majority of MPs. The two parties that have previously benefited from the FPTP's seat bonus in seats can't complain they are being treated unfairly. With one-quarter of the support in the polls, Labour gains a predicted two percent bonus in its share of the seats. The third-place Conservatives can still gain one-fifth of MPs with just over one-fifth of poll support.
With the current division of votes there is an 87 percent likelihood of the next general election failing to manufacture a majority of seats for any party. The most likely outcome of this month's division of the vote is a Reform Party that is 134 seats short of gaining the absolute majority needed to take control of government.
Arithmetic could justify the formation of a Coalition government with Nigel Farage as prime minister and whoever led the Conservative Party as deputy prime minister. On current showing, it would have an absolute majority with 334 MPs and a lead of 156 seats over Labour. Doing so would reduce the Tories to being a junior partner in government like the Liberal Democrats in 2010 and be opposed by Tories fearful of being relegated to minor-party status.
Labour risks paying the price for the Faustian bargain that delivered it control of government with the lowest plurality of the vote in British history. The February prediction shows that with one-quarter of the popular vote Labour could lose 234 of its MPs, including 157 that would go to Reform. The only way it could remain in government would in the politically impossible position of a junior partner in a Reform-led coalition government. A putative anti-Reform coalition of Labour and Tories would just lack a parliamentary majority.
It is politically possible to conjure up a Left Coalition government headed by Labour in partnership with the Liberal Democrats and the SNP. However, this would only have 287 MPs, falling far short of a Commons majority. Adding the Greens to create a four-party Left coalition would have 49 per cent of the vote, but still remain short of the 326 seats needed for a parliamentary majority.
A Parliament in which there is neither a majority party nor a coalition majority could lead to the prompt calling of another election. But well before that happens Keir Starmer has more than four years to turn the electoral system once more to Labour's advantage, as a five percent increase in Labour's current support could give it four-fifths more MPs than its present dismal prospect and five more years in control of British government. This is more than the four percent gain in support that Reform would need to form a majority government; however, it is much less than the nine percent gain in votes the Tories would need to add to their present support in order to achieve a parliamentary majority.
Prof Richard Rose, director of the Centre for the Study of Public Policy, University of Strathclyde Glasgow, is Britain's senior psephologist.