Four Fine Gael TD's will be thrown out of the party this evening when they defy orders to back abortion laws in the first Dáil vote.
However as many as ten TD's, including junior minister Lucinda Creighton, could refuse to back the legislation over a number of votes in the coming weeks.
Last night the Dáil debate on the Protection of Life During Pregnancy Bill came to an end with 94 TDs having had a say.
Four in Fine Gael, Terence Flanagan, Peter Matthews, Brian Walsh and Billy Timmins, say they will not support it in this evening's first vote which will result in their immediate expulsion from the Parliamentary Party.
But the threat that those who don't support the legislation in all votes will not be Fine Gael candidates at the next general election may not put off six or seven more from defying the whip.
They are holding out for amendments at committee stage, but ministers have warned there will be no substantive changes.
The Taoiseach Enda Kenny also said he could not remove the suicide clause as some demanded as he could not pick and chose which parts of the Constitution to uphold.