TV3/Millward Brown Poll September 2010 Overestimates Labour Party Support

On the face of it this appears to be an astonishing surge by the Labour Party. According to the poll Eamon Gilmore is also the most popular party leader for Taoiseach - 36% opt for him, compared to 19% for Enda Kenny and just 11% for Brian Cowen. Only 53% of Fine Gael voters opt for Enda Kenny as Taoiseach.
Undoubtedly the Labour Party has been gaining in popularity for the last year. However on closer scrutiny there appears to be a serious flaw in the methodology used in this poll. When the opinion poll contains dont knows the major parties support is as follows:

• FF 18%
• FG 25%
• Labour 29%
• Dont know 17%

Excluding Dont knows

• FF 22%
• FG 30%
• Labour 35%

Essentially the pollsters have reallocated the dont knows in very roughly the same proportion as the percentage for each party in the actual opinion poll.
In the poll Labour secured 29% of first preferences. The pollsters then reallocated 6% from the dont knows to the Labour Party. That is 35% of the total dont knows reallocated to Labour.
FF secured 18% of the vote in the poll. It was then re allocated 4% from the dont knows. That is FF was given 23.5% of the total dont knows.
FG secured 25% of the vote in the original poll. It was reallocated 5% from the dont knows. That is 29% of the total dont knows.
Quite frankly this approach is deeply flawed. Such has been the surge to Labour in recent months it is highly unlikely that many potential Labour voters would lurk in the dont knows column. For now it is fashionable to declare support for Labour. Labour is flavour of the month. Eamon Gilmore has benefited from largely kid glove treatment in the media.
In contrast Cowen and Kenny have been savaged. The reality is that the overwhelming majority of dont knows are FG and FF supporters reluctant to show their hand. It is not fashionable to declare support for either party. However that does not mean that it will not materialise in the privacy of the ballot box. In short the Labour Party support is overestimated in this poll. The FG and FF support is seriously underestimated.
In addition much of the Labour Party support is soft. Some of this will drift back to FF in the course of a general election campaign as Labour is forced drop its ambiguity on budgetary measures needed to tackle the deficit.
In short the poll has undoubtedly caught the Labour Party surge. However its reallocation of dont knows is flawed. Consequently it underestimates FF and FG support.