Twenty years ago it would have been unthinkable for a major trade union to promote a candidate in the hope of unseating an incumbent Labour MP, but today it is not so surprising.
In putting up RMT union representative Mick Tosh to challenge Sarah McCarthy-Fry in Portsmouth North, the Trade Union Socialist Coalition is clearly spelling out its wish to ring out the new and ring in the old.
Ring in Old Labour, that is, and ring out New Labour.
Before Tony Blair effectively re-invented the party in the 1990s, Labour policy was effectively established at the TUC rather than at the party conference because of the power of the trades unions' block votes.
To a union movement already bruised by Tory prime minister Margaret Thatcher's reforms, Mr Blair's transformation of Labour seemed like the final straw, and it was inevitable that at some point the left wing would seek to bite back.
And that is what is happening now, at the potential expense of Mrs McCarthy-Fry and some other sitting Labour MPs.
It may be that RMT man Mick Tosh, by standing in Portsmouth North, will simply hand the seat to the Tories, but that is itself a reflection of how times have changed: New Labour are seen as hardly less of an enemy.
Our purpose here is neither to endorse nor to denounce any party or any candidate, yet we welcome the intervention of the new socialist coalition in Portsmouth.
Let's face it, Mr Tosh has no realistic chance of winning, but he will help crystallise the debate about the direction of the Labour party.
He will also invigorate the whole campaign, and that is welcome because anything that militates against the apathy that remains an all-too-potent factor in British politics must be encouraged.
Minority-party candidates perform a vital service in raising public interest in elections, however slight their chances of success may be.
We look forward to an intriguing contest in Portsmouth North at the General Election.