Lise Hand: And then there were two -- the Old Hippy and Young Square
With nine days to the finish-line, it is (bar any last-minute game-changing upsets, alarms, controversies or revelations) a two-horse race.
But while there are clear political differences between staunch Labour comrade Michael D Higgins and "sporadic" Fianna Fail member Sean Gallagher, the starkest contrast is in their respective ages.
It is essentially an Old Hippy versus a Young Square. In one corner is 70-year-old Michael D, garrulous darling of the luvvies and eminence grise of the Oireachtas, and in the other is 49-year-old Sean, plain-speaking entrepreneur and businessman.
And as the field has essentially narrowed to a contest between these two candidates, it's become increasingly clear that Sean Gallagher is playing to this particular strength in order to compensate for the obvious weakness of his lack of experience in the political arena.
Bullet-headed and broad-shouldered, Sean exudes physical strength, even turning the fact that he is visually impaired into a campaign parable about how to overcome obstacles. He has an attractive wife, Trish, whom he married last year, and has said how he would like to be the first president to have babies crawling about the Aras.
"Please God, we're married now 14 months and it would be both our wish to start a family," he said recently.
In various TV debates and interviews, Sean rarely misses an opportunity to mention how he is "young" and "vigorous" and "full of energy", and this week he popped up in the papers sporting his Judo gear -- he's a black belt.
On the other hand, Michael D cuts no dash in the physical stakes; he walks with a slight limp after he fractured his knee in a bad fall while on a human rights mission in Colombia last year, although he is firm in his insistence that it's on the mend and won't make any difference to his ability to take on the gruelling job of president.
And perhaps Sean's continual references to his "vigour" are a tactic to attract the sizeable youth vote which has attached itself to the oldest candidate in the contest.
And there are signs that it may be beginning to work. The Red C poll last weekend which put Sean Gallagher into a surprise lead of 39pc over the former frontrunner Michael D's 27pc, showed that the Independent candidate was polling extremely well among females between 18 and 44, while Michael D was stronger among the over-65s.
Tellingly, there are signs that the frequent focus on his age are beginning to get to Michael D. In the early days of the campaign he laughed off questions on his age. "There isn't much I can do about it," he retorted spiritedly to one reporter.
But recently he's become tetchier on this delicate topic and last Sunday described as "crude" age comparisons between himself and Sean.
"I would regard that as deeply insulting, not only to me, but insulting to everyone over the age of 60," he declared.
Insulting it may be, but it's a tactic that may, if the polls are correct, have Michael D in the fight of his long life.