It had been billed as the most important election result in the party's history.
In the normal scheme of things, to say or suggest such a thing about one by-election would be absurd. But for Fianna Fail and its leader, Micheal Martin, given its disastrous track record in by-elections combined with sustained internal wrangling over poor opinion polls, the Carlow/Kilkenny race was that important.
It may very well be the race that saves Martin's job.
Former TD Bobby Aylward was picked to be the party's standard-bearer in this race to succeed former Fine Gael minister Phil Hogan and was the early favourite.
With him expected to take the seat, a truly disastrous run of form would end for the once omni-present party.
But those ongoing troubles within Fianna Fail, typified by the decision of John McGuinness, who is the party's only TD to go on a week's holidays during the campaign, saw Aylward's campaign retreat somewhat in the later days of the campaign.
But an Aylward win represents the first by-election gain for Fianna Fail since 1996, when Brian Lenihan and Cecelia Keaveney took seats when the party was last in opposition.
The 60-year-old conservative farmer isn't exactly at the cutting edge of new politics and won't be challenging for the party leadership anytime soon, but his win is incredibly significant for Fianna Fail.
It shows the party has a future and the win will undoubtedly give it a major boost to the heretofore disconsolate and dejected troops.
But, apart from the immediate win for Fianna Fail, just what does an Aylward win exactly mean?
Well, as the votes were tallied yesterday, a number of interesting trends as to voting patterns emerged.
Firstly, more than 60,000 voters who undoubtedly registered to vote on the same-sex marriage referendum also carried through and voted on the by-election.
In some areas, the by-election turnout was higher. This is very important. Secondly, while voters in huge numbers backed the liberalisation of marriage, they reverted in huge numbers to the traditional parties of Fianna Fail and Fine Gael rather than flocking to independents or new offerings like Patrick McKee of Renua.
Thirdly, it was clear that many people who gave their first preference to either Aylward or Fitzgerald, went on to give their second preference to the other. This was a clear attempt to stymie the rise of Sinn Fein's Kathleen Funchion.
She, however, performed well, and her transfers were key to the final result.
This is also significant and will leave political advisors scratching their heads as to where to pitch their campaigns for the General Election.
But the win for Fianna Fail does not mean all is well within the party.
As referred to above, Martin's capacity as leader is continually questioned, not just by so-called usual suspects like McGuinness but across the party.
The overly centralised, top-down style of his leadership infuriates many TDs and senators.
Of particular frustration is his perceived refusal to engage in the sort of all-out attack that defined Fianna Fail in opposition under Bertie Ahern ahead of the 1997 General Election, and was also the main tactic of then Labour Leader Eamon Gilmore before the 2011 election.
But worse still, the party is highly disjointed, with a small number of TDs like Dara Calleary, Billy Kelleher, Timmy Dooley and Niall Collins expected to carry the burden of representing the party across the media, while others rarely appear at all.
For Fine Gael, this result is a disappointment, given the man whose departure for Europe caused the by-election.
David Fitzgerald, who saw off the challenge of former IFA boss John Bryan to secure the party's nomination, ran an impressive campaign, even if his robust style grated with some. The feeling was he had to be well ahead of first preference votes in order to defeat Aylward, who was always likely to be more transfer-friendly,
When it emerged that Aylward was ahead by some distance in boxes from all parts of the constituency, the outcome of the election was becoming clear.
A 10pc vote for Renua candidate Patrick McKee shows that the party has realistic claims to some seats come the next election.
His party leader, Lucinda Creighton, only a couple of days ago said he would win the seat and in their first electoral test, Renua can be encouraged by their return.