Electoral forecasters are not sure what will happen next year. To some, a Conservative majority is the most likely outcome. To others, a Labour majority. Most point out the possibility of a hung parliament with either side as the largest party.
National opinion polls tell us something about how this might pan out, but they can only give us so much. This is not one election, but 650 small elections that will then give us a parliament. Of utmost importance will be those people who voted Liberal Democrat in 2010. Some will stick with the party. Others will switch to Labour, Conservative, UKIP, Green or one of the nationalist parties. Some will not vote. How many switch to which party, and in which constituency, will be crucial in deciding a number of marginals up and down the country.
The following Twitter exchange between Mike Smithson and the Electoral Forecast UK team summarises the debate well.
MS: New post Take LAB majority odds at 2-1 or longer – this is now a great value bet http://bit.ly/VFVxo1
EFUK: If you believe our odds (which you may not!), you shouldn’t take Labour majority at less than 2.84 to 1.
MS: So in effect you’re saying that 2010 LD-LAB switching won’t happen on anything like scale suggested by the pollsters. My reading is that in key marginals LD-LAB switchers are solid which makes a CON majority almost out of question.
EFUK: On LD-Lab switchers, clearly many will not return. But how many there are depends on which poll question you ask. Across all the Ashcroft constituency polls, LDs are polling 60% higher in “thinking about your const” q than in generic.
MS: The @LordAshcroft data shows more 2010 LDs saying they’d vote LAB on second (seat related) question than on first question.
EFUK: In Con-Lab marginals, you are right. In Con-LD and Lab-LD marginals, huge swings towards LD in second question. For Labour majority, the Con-Lab marginals are more numerous, and therefore important than LD-Lab, so I take your point there.
MS: That makes it worse for CON & possibly harder for it to pick up the number of LD seats that UNS (uniform swing) suggests they should.
The way in which 2010 Lib Dem voters vote in 2015 will be crucial in deciding who forms the next government. We can take it almost certainly as a given that some will switch. Some of them switched to Labour after the 2010 election, according to opinion polling, and most of those that did so appear to have stayed. If they continue that trend, then Labour looks set to win a number of Lab-Con marginals next year. However, if they switch to the Conservatives in the South West and South East, then the Conservatives could gain a few seats there as well. If they stay with the Liberal Democrats, then it could be very tight indeed.