UK General Election Forecast from ElectionsETC.com

The polls have moved slightly in Labour’s favour since last week’s debate. In our polling average, they’ve gone from one point behind the Tories last week (33%-34%) to one point ahead (34%-33%). The Lib Dems have also gained a point to 9%, their best since January, while the Greens seem to be fading, now on 4%.
Our model still makes the Tories the favourites to win the most votes, with a 66% chance of doing so (mainly due to their historic tendency to outperform the polls on election day). Our central forecast has them getting 34% to Labour’s 32%.
Their chances of winning the most seats are similar: 67%, and our central forecast now has them winning 23 more than Labour, 289-266, with the SNP on 49 and the Lib Dems on 22.
David Cameron’s chances of winning a majority have fallen back to 10%, while Labour’s are still less than 1%. The probability of a hung parliament is now up to 90% – our highest yet.
However, we have Ed Miliband back in front as the slight favourite to become Prime Minister, with a 56% chance that some combination of Labour, the Lib Dems, the DUP, the SNP, Plaid, the Greens, the SDLP and Lady Hermon will have 323 MPs between them.

Date of forecast: 10 April 2015
Days till the election: 27
Inputted current average poll shares
Con: 33%
Lab: 34%
LD: 9%
UKIP: 14%
Others: 10%
Forecast GB Vote Shares (with 95% Prediction Intervals)
Con: 34% (30% – 38%)
Lab: 32% (29% – 36%)
LD: 11% (7% – 15%)
UKIP: 13% (9% – 17%)
Others: 10% (8% – 11%)
Forecast Scotland Vote Shares (with 95% Prediction Intervals)
SNP: 46% (42% – 50%)
Labour: 28% (24% – 32%)
Forecast GB Seats (with 95% Prediction Intervals)
Con: 289 (246– 333)
Lab: 266 (225 – 305)
LD: 22 (12 – 32)
SNP: 49 (38 – 55)
PC: 3 (2 – 3)
UKIP: 5 (4 – 5)
Grn: 1
(May not sum to 632 due to rounding of sums of probabilities.)
Central forecast: Con short of a majority by 34
(Criterion for majority now changed to 323 not 326, assuming Sinn Fein win 5 seats and do not take them.)
Probabilities of key outcomes
Con most votes: 66%
Lab most votes: 34%
Con most seats: 67%
Lab most seats: 33%
Hung Parliament: 90%
… with Con largest: 57%
… with Lab largest: 32%
Probabilities of predicted government outcomes:
(See here for explanations and assumptions)
Con majority: 10%
Con+DUP: 7%
Con+LD: 13%
Con+LD+DUP: 14%
Con largest, but Lab+SNP+others maj: 18%
Con largest, but Lab+SNP maj: 6%
Lab largest, Lab+SNP maj: 9%
Lab+LD+DUP+SDLP+PC+Grn+Hermon: 7%
Lab+LD+DUP: 7%
Lab+LD: 7%
Lab+DUP: 2%
Lab majority: 1%

(Probabilities may not sum due to rounding)