As discontent in the party intensifies after a slate of poor showings in opinion polls, Mr Martin must lead the party to victory in the crunch Dáil showdown in May if he is to secure his job.
The byelection is set for May 22, the same day as the same-sex marriage referendum.
With the party flatlining in the polls at the 17% support it achieved in the 2011 general election, one TD said Fianna Fáil losing a seventh consecutive byelection would trigger a challenge to topple Mr Martin. “If we can’t win a single byelection, how are we going to make a comeback in the general election?” the deputy asked.
The next general election is likely to take place in the first half of next year.
Some in the party believe it would be better to leave Mr Martin in place for the general election so Fianna Fáil can then draw a line under that era in the next Dáil.
With chief whip Seán Ó Fearghaíl branding the situation “depressing” and “bloody demoralising”, TDs are openly nervous ahead of the looming byelection.
Willie O’Dea, a former minister, insisted that voters were more favourable to the party now than four years ago, pointing to a reduction in the level of “hostility” he receives on the doorstep.
Mr O’Dea put the poor poll ratings down to a general disenchantment with politics and a more crowded field. The Limerick TD pointed out that the party was the biggest vote-getter in last year’s local elections with 25%.
With Fianna Fáil struggling to stay in double figures in Dublin, Mr Martin faces a further blow as a prominent former party candidate is threatening to stand as an independent at the next election.
David McGuinness, who was deselected as the party’s candidate in Dublin West after finishing second in the seat in two recent byelections, said he was considering going solo.
Such a move could rob the party of taking a seat in the late Brian Lenihan’s constituency — the only area in Dublin where Fianna Fáil delivered a TD in 2011.
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