Putting the national interest first. Playing the 'Responsible Party' role. And providing stability through the stormy Brexit waters.

These were three of the well-rehearsed reasons given by Fianna Fáil for chewing the Fine Gael wasp and remaining in the unorthodox Confidence and Supply arrangement for nearly four years.

Keeping Fine Gael in Government was hard for dyed-in-the-wool Fianna Fáilers to stomach since 2016. Now some of the party’s candidates are hearing about it on the doorsteps.

Four opinion polls have suggested Fianna Fáil is ahead of Fine Gael.

Polling three points ahead of Fine Gael in the Red C/Sunday Business Post poll, marked the first time since April 2017 that Fianna Fáil polled ahead of Fine Gael in that series of polls.

The margin of error is plus or minus 3%, so it is all to play for with 12 days left until polling day.

Several Fianna Fáil figures say that they are pleased with the reception they are getting on the canvass trail, but one issue is causing them some concern – the Confidence and Supply deal.

They say that they are getting a lot of people criticising them for supporting Fine Gael from the opposition benches for so long.

One outgoing TD is repeatedly asked on the canvass trail why Fianna Fáil did not challenge Fine Gael more?

He said it is a really unprecedented situation to be out canvassing, after nine years in opposition, and finding himself under attack for decisions made by Government.

This mood on the doorsteps could be feeding into the increased mud-slinging between the two largest parties in recent days. Any pretence of co-operation that was created over the last four years needs to be eradicated.

This morning Fianna Fáil's Michael McGrath cranked things up when he accused Fine Gael of playing dirty and running a Trump-style "operation fear" in this campaign. This comes as a number of Fine Gael candidates attacked Fianna Fáil.

Fine Gael parliamentary party chairman Martin Heydon rejected the "project fear" jibe from Mr McGrath and said: "It’s pretty incredible that they have issued their manifesto last Friday and they have since refused to put forward any detailed costings or financial background to that."

He said he cannot believe Micheál Martin will go on tonight’s Claire Byrne Live debate without having those costings published.

"Either they don’t have their figures worked out or worse again they do and they are not very confident in them and they just don’t want to show them."

Earlier today Fine Gael’s Peter Burke claimed Fianna Fáil it seems "is caught between a rock and a hard place: they want to appear prudent and responsible, but they can’t help their natural inclination, which is to make an unending series of reckless spending promises."

This friction between the two largest parties is likely to escalate at tonight’s debate in NUI Galway.

The Fine Gael leader Leo Varadkar conceded at the weekend that in hurling terms his party is three points behind at half-time but he insisted it can be turned around.

If this debate marks the start of that second half, then Leo Varadkar will need to hurl well tonight. Expect the Fine Gael leader to continue with a strategy of claiming that Fianna Fáil cannot be trusted at the public finances tiller ahead of Brexit.

Mr Varadkar will be facing attacks from the other six party leaders for his party's record in Government over nine years.

Like those people on the doorsteps taking issue with Confidence and Supply, we can expect five of the party leaders – Mary Lou McDonald, Brendan Howlin, Richard Boyd Barrett, Roisín Shortall and Eamon Ryan – to adopt similar arguments tonight in Galway.

With a seven-way debate it also likely that is something unexpected that will grab the post-debate headlines.