There are still two and a half weeks of the campaign to go before polling day, but postal votes are already being sent out to voters and many have already made up their minds. We believe there is now a small range of likely seat outcomes, and therefore possible governments.
Our central case sees the two main parties almost level on seats, resulting in a Labour minority government dependent on the support of the SNP and its allies (the Greens and Plaid Cymru). Slightly different outcomes are also possible, depending on the final size of the swing from the Conservatives to Labour in England and Wales, over which there is still considerable uncertainty. If Labour does worse than we expect, it could require the votes of the Lib Dems as well as the SNP; if it does better, it could require only Lib Dem votes.
The upside case for the Conservatives is now that they win enough seats to make a minority government dependent on the support of the Lib Dems, DUP and UKIP possible. We think that scenario is now unlikely, but even if it were to occur, we think it would be very challenging to both knit those parties together and persuade the parliamentary Conservative party that its interests are best served by doing so. For these reasons, we think a government led by the Conservatives can now be all but ruled out.