Um, could I kindly ask for another recap of the differences between the Irish parties please?
Fianna Fáil: Centrist to centre-right, populist, conservative. You could make an awkward comparison with some of those conservative Democrats in the Southern US.
Fine Gael: Centre right, more economically liberal than Fianna Fáil, arguably more socially liberal.
Labour: Centre left.
Sinn Féin: Supposedly socialist but really a single-issue party based around a united Ireland.
Socialists: Stunningly, far left.
Oh, wait, let's not forget Libertas! *collapses laughing*.
A general rule of thumb is that Labour do very well in urban areas while Fianna Fáil and, to an extent, Fine Gael do better in rural areas where no-one would vote Labour if you paid them.
You forgot (probably intentionally) the Greens.