It's very early days in these counts but telling patterns are emerging.
The first is the sustained momentum of the Green vote, which looks set to deliver the party its first ever by-election win, in Dublin Fingal.
Sinn Féin's really strong showing in Dublin Mid-West has put it in contention to win a seat there.
The party's vote both there and in Cork North Central suggests it has arrested the serious recent slide in its support levels.
Also it demonstrates a renewed ability to get the party's vote out, something it failed to do in the local and European Parliament elections.
For Fianna Fáil the day looks to have the potential to deliver on its privately held target of winning two seats.
Anything less would be something of a disappointment though.
A win in Cork North Central and Wexford looks possible, although Fine Gael are still in the hunt in Wexford.
But a win there could pose its own problems for Fine Gael, given Verona Murphy's controversial comments on asylum seekers during the campaign.
Although she apologised for those remarks, if she was successful it would be viewed by many as permission to raise the asylum seeker issue repeatedly in the next General Election campaign.
For the Labour Party, it appears the optimism of those within the parliamentary party about the by-elections was somewhat overstated.
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