The next UK general election is set for 12 December 2019 and an analysis of the latest UK polling data currently predicts a Conservative and Union Party (aka Tory Party) victory with 39.7% of the overall vote.
Electoral Calculus, founded by algorithm and modeling expert Martin Baxter, has published its predictions following a review of opinion polls, "from 01 Nov 2019 to 09 Nov 2019, sampling 8,210 people".
Though the analysis makes clear that nothing is set in stone, as was proven by the Labour Party doing better than predicted in the 2017 general election, the current polling data analysis predicts that the Tories will secure 382 seats, compared to 185 seats by Jeremy Corbyn's Labour Party, 42 by the Scottish Nationalist Party (SNP), 20 seats by the Liberal Democrats, and 1 seat by the Greens. The Welsh nationalist party Plaid Cymru are currently predicted to go down from 4 seats to 2, while the DUP Protestant Nationalist Party from the North of Ireland are predicted to lose one seat bringing them down to 9.
The "poll of polls" initially had Tories securing a 76 majority on 30 October but that has increased to 114, according to the latest assessment published on 12 November.
One factor influencing the prediction of a loss of seats for Labour (compared to the 2017 general election) is that, "Remain supporters are still split between Labour and the Liberal Democrats", according to Electoral Calculus.
In October 2019 Electoral Calculus noted that there are, "three main factors which could change this prediction: pollster error, campaign swing and tactical voting".
UK elections are based on the first-past-the-post system, which means that the candidate which gets the most votes in a constituency wins, even if most people didn't vote for them. Which means that tactical voting is a big part of what influences many voters' decisions in the final hours at the voting booths. So much so that websites such as Tactical Vote have been established to help people "Stop the Tories" by tactical voting.
Electoral Calculus explains that:
"Although the parties are unlikely to co-operate, we may see voters vote tactically to support Remain-leaning candidates against Leavers. This factor could change the result in many marginal seats, and there are far more marginal seats than usual this year".
"The pollsters have got it wrong before", they write, "and they can't all be right now because there are big disagreements between them".