FRIDAY 11 March has been earmarked in government circles as the likely date for the general election, allowing for what will effectively be an eight-week campaign beginning when the Dáil resumes in the middle of January.

A beleaguered Fianna Fáil is keen to have a long campaign during which it believes it can benefit by highlighting the policy gulf between Fine Gael and the Labour Party, targeting both Enda Kenny and Eamon Gilmore.

Green Party leaders are under huge pressure from members to push for the earliest possible date. But they are committed to seeing through the finance bill – which is thought unlikely to happen until the second week in February – and four key pieces of Green legislation. While the election campaign will not technically begin until the dissolution of the Dáil – after the finance bill is enacted – the electioneering will be ratcheted up once the Dáil resumes on 12 January.

"It will be a long, long campaign. Once Christmas is over, it'll start," one senior government deputy said yesterday.

One option being mooted is that the Taoiseach may announce in January the enactment of the finance bill by a certain date in February and then formally seek a dissolution of the Dáil.

Such an announcement would have the effect of artificially lengthening the campaign, giving the longest possible run-in until polling day for Fianna Fáil to target the opposition.

Legislation limits the time between the dissolution of the Dáil and polling day to 25 days, excluding Sundays.

Informed sources said there was no realistic prospect of the finance bill being completed by the end of January, as considerable time is required for the committee stages and inevitable re-drafting. The belief is it can be completed by the second week in February.

If the Dáil is then dissolved, a 25-day campaign would see the election being held on Thursday 10 March or Friday 11 March – now widely regarded in government circles as the most likely election dates. It is understood the government is currently leaning towards a Friday election.

Fianna Fáil would like to push the date out even further. But the following week is a complete non-runner because it coincides with St Patrick's Day. The 24/25 March cannot be entirely ruled out, but the Green Party is unlikely to be keen on leaving it that long and certainly won't consider an April or May date, as advocated by some in Fianna Fáil.

The Greens are keen to see the passing of the Dublin mayoral bill, the ban on corporate donations, the climate-change bill and the waste-levies bill – which will allow for levies on incineration and is of particular local importance to environment minister John Gormley – before leaving office.

There was speculation last week that the sections of the climate-change bill dealing with agriculture will cause problems for Fianna Fáil deputies and could cause problems within government, but this was played down by sources in both government parties.