A new analysis by Oxford academic Stephen Fisher (a member of the team which was behind the scarily accurate BBC/ITN exit poll at the 2010 election) douses the comfort blanket to which many of us Lib Dems have been clinging, suggesting as it does that the Lib Dems are losing more votes in our strongest seats:
The most significant factor affecting party performance at the constituency level is prior Liberal Democrat strength. … the Liberal Democrats are clearly loosing most in the seats where they started strongest and losing least where they started weakest. Partly this is inevitable. There are over 100 seats where the Lib Dems got less than 16% of the vote in 2010 and so their vote share cannot fall by this much. Moreover it is unlikely that the party will fall exactly to zero even where it does very badly. So if the GB polls are right overall, the Liberal Democrats must be falling more where they started stronger, and the BES data suggest the drop is broadly proportional to their prior strength. This mirrors the pattern of change at the local authority level at the European Parliament elections this year, adding confidence that the effect is real. The implications for Liberal Democrat seats are straightforward. If they are indeed losing most heavily in the seats they are defending they are set to lose several more seats than national polls with uniform swing would predict.