It was probably the furthest thing from her mind at the time, but Mary Harney’s bombshell decision to quit as leader of the Progressive Democrats has unleashed a chain of events that promises to inject real excitement into Irish politics. In the process she has shattered many of the assumptions that were set to govern the next general election campaign.

Harney’s decision has introduced a degree of uncertainty that will unsettle all the main political players, while entertaining those of us who consider politics a spectator sport. For the next few months we will have to speculate about all sorts of fresh questions. Some of them will be resolved quickly; others will unwind slowly.

The immediate decision is to find a replacement party leader. Harney has insisted that she will not canvass either for or against any of her colleagues, but, as of yesterday, this seemed to make no difference to red-hot favourite Michael McDowell.

The justice minister can see his prize, but would the election of Liz O’Donnell, given her record on foreign aid, soften the perception of the PDs as harsh and uncaring? Or does anyone care? Her picture would look better on election posters than McDowell’s, but that consideration, and former farmers’ leader Tom Parlon’s ability to attract a hitherto untapped rural vote, has been discounted.

If McDowell gets the nod, will he let Harney keep her job as health minister? And are his ideas radical enough to lift the fading chances of the PDs remaining a relevant force in Irish politics?

There are equally important questions to be asked about the relationship within government between the two coalition partners. If McDowell, as PD leader, assumes the role of tanaiste, how will he get on with Bertie Ahern? What stunts will McDowell devise to maintain the PDs’ individual entity in the coalition?

Will he pull the plug on Ahern at a time convenient to his own tactical vagaries, or will the taoiseach get him first? And if the 1% possibility that McDowell doesn’t get Harney’s job transpires, will he storm off in a huff, leaving the PDs high and dry and bereft of intellectual heft?

The more you consider it, the more questions arise. Fine Gael’s plans for an electoral comeback will be ruined if the middle classes turn to the right-wing populism of an emboldened McDowell. Fianna Fail, already damaged in the eyes of some potential voters because of contamination caused by prolonged proximity to PDs, could suffer further if it is believed to be endorsing the supposedly harsher ethos of McDowell.

Just a few days ago the feeling was growing that the government’s chances of being returned to power next year were negligible. At best, the Fianna Fail side of the coalition was resigned to forging an alliance with a new partner. The PDs, a small party that has always punched above its weight, was being measured for a funeral shroud. The odds are still stacked against it, but with a change at the top the new, improved PDs have a chance of remaining relevant.

It is dangerous to assume too much in politics, but at this stage we must assume that McDowell will be the next leader of the PDs — his colleagues will probably be too afraid to tell him, even in a secret ballot, that he can’t have the job.

Despite his many flaws, he is the pick of the small PD bunch. Success would elevate him to the highest position that he could reasonably have imagined, second only to the taoiseach in terms of power. The bad news is that the position will only last nine months — if that. But that short taste of power, coupled with McDowell’s desire to prove that his own brilliance can overcome crippling electoral odds, could be just the motivation he needs to wind up his troops for the coming battle.

We know already that McDowell and modesty are barely on nodding terms. You will recall that he attributed the unexpected success of the PDs in the last election to his brilliant idea to climb a lamppost in Ranelagh, from which he urged the public to elect his party as guard dogs who would prevent Fianna Fail from getting an overall majority.

Every PD failure of the past decade has been laid at the door of Harney or her accomplices. But every success, in McDowell’s mind at any rate, has been a result of his genius. McDowell believes that he and his political acumen are the party’s greatest asset. And he may be right.

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