The government is on course to lose a record 35 seats in the next general election, a detailed study of voting patterns in the local elections has shown.

An analysis by the Sunday Tribune of the results in all the 268 electoral districts in the state demonstrates that Fine Gael and Labour would win a huge majority of 32 seats if the results were replicated in a general election.

The study shows government losses on a scale that would be unprecedented in the history of the state.

Fianna Fáil would lose 27 seats from its 2007 general election result, including high-profile ministers such as Mary Hanafin, Barry Andrews, Pat Carey and Peter Power. The party would be left with just 52 TDs, by some distance its worst return in a general election since the 1920s.

The voting patterns in the locals show Fianna Fáil failing to win any seats in two constituencies, Dun Laoghaire and Dublin North-West, another unwanted first for the party.

The Green Party faces wipeout, losing all its six seats, with cabinet ministers John Gormley and Eamon Ryan failing even to come close to being elected if the party's vote in the locals remains at that level.

The government would also fail to hold the seats of independents Mary Harney and Jackie Healy-Rae. Fine Gael would dominate the new government with 69 seats – just one seat behind its best ever return of 70 under Garret FitzGerald in the election of November 1982.

Labour would jump 10 seats to 30 TDs, just shy of the amount it won in the 1992 'Spring Tide'. On that basis, the party would probably be in line for five ministers at cabinet, compared to Fine Gael's 10.

Despite the government parties' collapse, there would be no breakthrough for Sinn Féin, which would pick up just one additional seat. Joe Higgins' success in the recent European elections would be replicated with both he and Socialist Party colleague Mick Barry, in Cork, taking seats.

The results show the huge deficit that Taoiseach Brian Cowen has to overcome if Fianna Fáil is to retain power in the next general election. On this evidence, Fine Gael and Labour could afford to miss out at least 16 of their realistic targets and still form the next government.

The study indicates that a FF-Labour government would be numerically possible. But, in practical terms, it would be impossible for Labour to go into coalition with Fianna Fáil, rather than Fine Gael, when Fianna Fáil had been so firmly rejected by the electorate.

The Sunday Tribune study involves strictly applying voting across all electoral districts into Dáil constituencies to assess how the parties would fare in a general election scenario. No allowance is made for high-profile names – it is a straight mathematical exercise of applying the local election figures to a general election setting. The study represents a de-facto general election opinion poll of over 1.85 million voters.

Meanwhile, Taoiseach Brian Cowen will not make any changes to his cabinet until after the conclusion of the programme for government renegotiations and the holding of the Lisbon referendum, according to sources.

While there has been intense speculation about a cabinet reshuffle, focusing in particular on enterprise, trade and employment minister Mary Coughlan, it is understood that it is by no means certain that there will be any such moves.

Cowen, who places a strong premium on loyalty, would be reluctant to do anything that would be seen to scapegoat his Tánaiste for the unpopularity of the government.

Sources insist nothing will happen ahead of the Lisbon referendum, which is likely to be held in October. Cowen is determined to mount a serious and professional 'yes' campaign and a reshuffle would be a distraction that would risk alienating ministers who will be expected to play a key role.

By the time the referendum is over, it will be just weeks to a budget that is likely to be hugely contentious. That suggests that a reshuffle is unlikely to happen before the end of the year.