Original sentence: Eight of the eighteen MPs elected from Northern Ireland are Catholics.Electorally, while voting in Northern Ireland tends to follow religious lines, (the Democratic Unionist Party has no Catholic members, the Ulster Unionist Party has a relatively small number) no such religious demarcation exists in the three Ulster counties in the Republic of Ireland
Edited sentence: Eight of the eighteen MPs elected from the six counties of Northern Ireland are Catholics.Electorally, while voting in the six counties tends to follow religious lines, (the Democratic Unionist Party has no Catholic members, the Ulster Unionist Party has a relatively small number) no such religious demarcation exists in the three Ulster counties in the Republic of Ireland