Under single constituency first past the post system national aggregate vote totals don’t mean that much
Why the legitimacy of what could appear a perverse general election outcome cannot be questioned
There’s lots of talk at the moment about the electoral “system being bust” and “no longer fit for purpose”. What is being pointed to are possible disparities between national aggregate vote shares and the total of MPs each party gets.
Clearly in what is now a four party structure it is very likely that many seats will be won with the victor securing fewer than 30% of the votes. Until the post referendum LAB Scottish collapse it was possible to envisage LAB securing an overall majority with, perhaps, a third of the national aggregate vote.
In 2005 Tony Blair secured a comfortable overall majority for LAB with just 35.2% of the UK vote or 36.2% excluding Northern Ireland.
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But much of this is the product of a voting system that forces those who wish to influence the outcome not to vote for their allegiance but to choose between the two top choices in their particular seat who can possibly win
To many , in any case, their vote is for an individual not a party or a potential prime minister. Incumbency can be a key element thus undermining a bit further the idea that national party totals are important.
Thus, to take one of many recorded examples, we see from the Ashcroft marginals polling that in seats where the effective choice is between blue and yellow that 17% of LAB voters will switch to back the latter. They maybe doing this because they are happy with their sitting MP or they want to stop the Tories. Whatever their actions depress the overall LAB vote share but it does mean that these voters can have an impact on the election. The alternative is for them to accept that their first choice is pointless in their seat and waste their votes.
One of the reasons why the Tories seem to do worse under the system is that, in the past, they have been much less likely to vote tactically than LAB voters even where their party does nor have a chance
- If the legitimacy of the outcome of a general election is questioned on national aggregate votes share grounds there is one simple response – the legitimacy derives from the nation voting overwhelmingly in May 2011 to retain the first past the post system.
A direct consequence of that result is that national aggregate vote totals can not be said to reflect what voters’ first choices are. So you cannot draw many firm conclusions from them.
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