Mr Mainstream Unionist is alive and well. He just stopped voting
It's hard to find any party in Europe which has managed to self-destruct as much as the Ulster Unionists have in the past 40 years.
This was brought home to me recently as I thumbed through a dusty old copy of Northern Ireland - A Political Directory, compiled many years ago by the BBC's legendary political correspondent, the late W D Flackes.
The appendix sets out the stark statistics of the unionist voting habits from the start of the Troubles. In 1970, for example, a single Ulster Unionist party polled 422,000 votes in that year's Westminster election and Ian Paisley's fledgling Protestant Unionists attracted only 35,000 votes.
By 2010, the Ulster Unionists were down to only 102,000 votes and the Democratic Unionists polled 168,000. Even taking Jim Allister's TUV and Lady Sylvia Hermon in North Down into account, around 100,000 unionist votes have still gone missing in the past 40 years.
How the mighty have fallen. The challenge now for the two contenders for the Ulster Unionist party leadership, Tom Elliott and Basil McCrea, is somehow to find a political strategy to reverse such seemingly unending decline.
So who is Mr Mainstream Unionist: the man whom the new leader needs to have on his side? What are his views and beliefs, prejudices and hang-ups?
Unfortunately for both leadership candidates, Mr Mainstream Unionist is likely to be in the DUP today and not in the UUP at all. He may view the UUP as wishy-washy, pseudo-liberal, rudderless, forsaking its cultural roots and not worth voting for anymore.
There was a time when he would never have thought of voting for anyone other than an Ulster Unionist. Now he doesn't bother to vote at all, or has found a new home for his political and cultural allegiance.
If he lives east of the Bann, there's only a 50-50 chance he will vote. If he lives west of the Bann, he is more likely to turn up at a polling station.
Mr Mainstream Unionist is half-hearted and unconvinced about the Stormont Executive. He remains deeply distrustful of Sinn Fein.
At times he is apoplectic about Caitriona Ruane. He regards Gerry Adams and Martin McGuinness more as closet terrorists than acceptable political leaders.
His children may be the lost generation of young unionists who have gone to university or work in Scotland or England and are unlikely ever to return.
He knows as little about gaelic football or hurling as he does about the Magillacuddy Reeks. If he goes to the new Aviva rugby stadium in Dublin, he'll join in the chorus of the Fields of Athenry, but remain tight-lipped for the Soldier's Song.
Thrift and sobriety still play a big part in his life. He pays his TV licence on time and is unlikely to default on his mortgage.
He does not want to live beside nationalists anymore than they wish to live beside him, but he wouldn't say so publicly.
Remembrance Sunday holds an emotional attachment for him. It annoys him that so many Catholics show little or no interest in it.
He has come to accept power-sharing at Stormont only reluctantly. He still cringes at the sight of Sinn Fein ministers officiating at public ceremonies.
He tolerates President Mary McAleese's frequent visits to Northern Ireland, but couldn't care less about life in the Republic. He can barely name a government minister from the south other than Brian Cowen.
Mr Mainstream Unionist wants unionist unity, not disunity. He's appalled at the prospect of Martin McGuinness as First Minister, but is at a loss as to how this can be prevented.
All in all, Mr Mainstream Unionist has far more of Tom Elliott in him than he has of Basil McCrea. Yet will either really make any difference to the inexorable decline and fall of the Ulster Unionist party? This is the party's moment of truth. A moderniser will take the party further away from Mr Mainstream Unionist. But will the traditionalist take it far enough in the other direction to make any difference?
On one fundamental issue, both contenders appear agreed. No merger with the Democratic Unionists. The statistics of voting in W D Flackes' old book - 422,000 down to 102,000 now - suggest to me they are both wrong. The missing tens of thousands of Ulster voters are mostly Protestants and unionists. Will they ever return to the fold?
Perhaps the long-term salvation for the Ulster Unionists, for the DUP and unionism in general, is to think the unthinkable and arrive at some form of new alignment between them all.
You may not like the image I've painted of Mr Mainstream Unionist, but he's alive and well.