Setting aside the "politics" of what one drinks, in most Irish households one is apt to encounter one (or more) of the following brands:

Paddys; Jamesons; Powers.

Middleton is a premuim brand and not much seen in the average Irish home. Bushmills is Northern Irish, and again not oft seen in the average home in the Republic.

There is a conceit that Paddy's is a working class whiskey, while Jameson's is linked to the ascendancy and Powers' is middle-class Dublin. In truth, it is really a matter of taste and price, with Paddys being the least expensive of the the three and Jamesons the most expensive. There are other brands, but these aren't as popular locally as they are in the export markets-- Tullamore Dew being a good example. You'd have to look hard to find a jug of Tullamore Dew for sale anywhere outside of Dublin Duty-Free at the airport.

The Irish also drink a lot of Scotch-- about 20% of all whiskey sold in the Republic comes from Scotland. The Big Three (Paddys, Powers, and Jameson) still dominate, and account for about 60% of all Irish whiskey consumed.

Although I always kept a bottle of all three popular brands-- and a Bushmills for visiting Americans-- at my home the most popular tipple seemed to Jamesons, closely followed by The Famous Grouse.