Shades of Frank Drebin: Gordon Brown may have sunk his chances in Britain’s general election with an unguarded comment into a microphone he didn’t realize he was still wearing. After campaigning in Rochdale in northern England, he muttered, amid a stream of invective directed at his aides, that 61-year-old Labour supporter Gillian Duffy was a “bigoted woman” for questioning him about the impact on the British job market of immigration from Eastern Europe.

Brown’s since made an in-person apology and e-mailed a fulsome “personal” letter to all Labour activists, but the damage seems to have been done. As one commentator put it, showing a nice grasp of British understatement, “I don’t think it’s a good idea to call voters bigots.”

On one level, of course, it’s possible to have some sympathy for Brown. This is the kind of thing that happens when you’re around microphones so much: few of us would want our every comment recorded and aired in prime time. On another level, as Andrew Rawnsley points out, this is just another example of one of Brown’s more unattractive attributes: his volcanic temper and his eagerness to pour vitriol on his aides and anyone else who gets in his way.

But this isn’t really about Brown’s bad luck or his bed temper. Poll after poll shows that immigration is a central issue in the election, or at least a central concern for many voters. There is every reason to believe that it lies behind the erosion of Labour support in places just like Rochdale, where many — like Mrs. Duffy — believe privately that the Labour elite view their concerns with contempt. Brown’s outburst is evidence that they’re right.

Not that more evidence is needed. Back in October, Andrew Neather, who was closely involved in the making of policy on immigration in the early Labour years, was sufficiently outraged by the televised appearance of Nick Griffin, the leader of the British National Party, to make the following case — and yes, he did think he was making the positive case — for mass migration:

[T]he deliberate policy of ministers from late 2000 until at least February last year, when the Government introduced a points-based system, was to open up the UK to mass migration. …

It’s not simply a question of foreign nannies, cleaners and gardeners — although frankly it’s hard to see how the capital could function without them. Their place certainly wouldn’t be taken by unemployed BNP voters from Barking or Burnley — fascist au pair, anyone? …

I wrote the landmark speech given by then immigration minister Barbara Roche in September 2000, calling for a loosening of controls … the earlier drafts I saw also included a driving political purpose: that mass immigration was the way that the Government was going to make the UK truly multicultural. I remember coming away from some discussions with the clear sense that the policy was intended — even if this wasn’t its main purpose — to rub the Right’s nose in diversity and render their arguments out of date. …

But ministers wouldn’t talk about it. In part they probably realised the conservatism of their core voters: while ministers might have been passionately in favour of a more diverse society, it wasn’t necessarily a debate they wanted to have in working men’s clubs in Sheffield or Sunderland.

The only thing more arrogant and out of touch than Neather’s acknowledgement that Britain’s immigration policy was covertly run for the benefit of those who employ foreign nannies was his slap at the “unemployed BNP voters from Barking.” His was the worst possible defense of mass migration into Britain because it was so obviously elitist. And all it really did was display at greater length the contempt that Brown spat at his aides and, unknowingly, into the microphone on Wednesday.

And that is the real political significance of Brown’s open-mike flub: it reminded a significant element in the core Old Labour vote — the vote Labour has to win if it’s to have any chance of playing a role in government-making after May 6 — that quite a bit of New Labour’s leadership quietly detests them and regards them as bigots.

Curiously, the real loser in this may be Nick Clegg, the Lib Dem leader, not Gordon Brown. Neither Clegg nor Brown was ever going to form a government on his own, but Clegg badly needs Labour to do well enough to keep the Tories from winning. Every alienated Labour voter that stays home is another constituency that’s in play for the Tories, and therefore another nail in Clegg’s chances.