The Deputy had been ranked at 4th.
A midlands TD has slipped to fifth in the odds to become the next leader of Fianna Fáil.
Laois Offaly Deputy Barry Cowen's odds have fallen from 7/1 to 8/1 in BoyleSports' latest ranking on who's most likely to take over from Micheál Martin.
Michael McGrath has claimed the top spot from Jim O'Callaghan, and sits at 7/4.
Dara Calleary and James Lawless round out the top five.
The latest betting trends have also given the current Fianna Fáil leader and Tanáiste 3/1 odds to become the next EU Commissioner.
Lawrence Lyons, Spokesperson for BoyleSports commented:
"Rumours linking Micheál Martin with the big job in Brussels just won’t go away so we’re taking no chances as more and more believe changes are afoot."
Micheál Martin Future
1/4 To lead FF into next general election
3/1 To be next Irish EU Commissioner
Next Fianna Fáil Leader
7/4 Michael McGrath
9/4 Jim O'Callaghan
5/1 Dara Calleary
6/1 James Lawless
8/1 Barry Cowen
9/1 Jack Chambers
9/1 Darragh O'Brien
12/1 Norma Foley
14/1 Thomas Byrne
14/1 Niall Collins
100/1 Bertie Ahern
Next President
4/1 Mairead McGuinness
7/1 Fergus Finlay
8/1 Bertie Ahern
12/1 Miriam O’Callaghan
33/1 Ryan Tubridy
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