Kenny Farquharson: Johnson has class to save Labour

I'M COMING round to the view you sometimes hear from people who are scunnered about politics, that if someone expresses an ambition to become prime minister then it should automatically disqualify them from the job.

Ambition and lust for power, the argument goes, are hardly the most reassuring qualities in someone you are going to entrust with your liberty, security and prosperity.

By this measure the ideal candidate for PM is Alan Johnson, increasingly the man on whom a desperate Labour Party is pinning its hopes of avoiding a cataclysm at the general election.

Johnson has spent much of the past few years explaining why he isn't up to being prime minister. He once described the chances of him getting the top job as akin to a beagle making it to Mars. On Desert Island Discs, asked why he didn't go for the leadership after Tony Blair resigned he confessed: "I don't think I would have been good enough, frankly. I don't think I've got the capabilities." Recently, he said that Gordon Brown would do a far better job than he ever could.

And yet…

Last week Johnson made what can only be described as a naked bid for power. He did so in a way that wouldn't have been possible a year ago, when the potential contenders for the Labour Party leadership all seemed to be occupying exactly the same political ground (a small scrap of New Labour pragmatism, unmoored and drifting in a sea of voter apathy).

Johnson, more than anyone on the front benches of any of the main parties, has grasped the fact that our politics requires a revolution if it is to recover the trust of the voters. And so he has proposed a raft of constitutional reforms that are currently the most radical on the table: a referendum on electoral reform, to be held on the same day as the next general election; a written constitution; fixed-term parliaments; reform of parliamentary procedure; elections to the House of Lords.

Policies, however, are only the half of his appeal.

I've long admired Johnson, as much for his personable manner and personal style as his politics. Back in the 1960s, when he was the guitarist in a mod band called The Area – dressed in a parka and Ben Sherman shirt and playing a sunburst red Hofner VeryThin semi-acoustic – one of the band's cover versions was Time Is On My Side. Well, it proved to be prophetic. This could very well be Alan Johnson's time. There's still something of the mod about him – one commentator once described him as "the first front-bench politician in history who can wear dark glasses without looking like a plonker, a contract killer, or blind".

In an interview a couple of years ago he was asked to compare himself with Brown, who is one year younger. "Of course, I have the advantage. I look younger than him and I'm better-looking," he said. "My ties are silk. Gordon's are polyester." What's not to like?

I'm not at all convinced that Johnson, if he replaced Brown this autumn, could save Labour's neck at the general election next year. But he could well do considerably better than Brown.

As a result of the expenses horrors our politics is in a state of flux. No-one can be certain where it will take us. I'm pretty sure, though, that what people will be looking for come voting day is not a tortured economic guru; not a facsimile Blair; not – god preserve us – Esther Rantzen. No, they'll want a politician they can look in the eye and see, reflected back at them, someone recognisably human. Someone with character. Someone who is part of the system but not owned by the system. Someone who doesn't look and act like a politician. Now, who fits that bill?

Johnson's back story is as good as it gets. His father, a painter and part-time pub pianist walked out of the family home when he was eight. His mother died when he was 12, and he was then brought up by his teenage older sister in a council house in Battersea.

This is a man who left school at 15 to pursue a dream to be a rock 'n' roll star. After this foundered - a thief stole all his band's gear and they couldn't afford to replace it – he took a job as a postman. (He has since joked that he is the only minister with previous experience of emptying red boxes.)

Like Brown and David Cameron, he has experienced the tragic death of a child - a daughter, Natalie, died of a blood disorder aged 30.

Crucially, Johnson has come out of the expenses scandal with relatively clean hands. And his impeccable working-class credentials will do him no harm at all as the public continues to vent its anger at the Tory predilection for moats, swimming pools, duck islands and rolled paddocks. The scandal has opened up a new front in the class war.

Johnson has political courage – when he was head of the Union of Communication Workers he took a huge amount of stick from his fellow union leaders for backing Blair's move to abolish Clause Four of the party's constitution. Politically he is a Blairite reformer, but not a docile one. He infuriated Blair when he ditched the government's plans to raise the public sector pension age from 60 to 65.

When he made his unsuccessful bid for the deputy leadership of the party in 2007, Johnson's slogan was "neither old Labour nor new Labour but real Labour". It seemed a little hackneyed then. Maybe it still is. But now, with the party battling for electoral survival, it is looking a lot like Labour's last hope.

One anonymous MP was quoted last week as saying: "Alan Johnson would save us 100 seats."

That may be wishful thinking. But Johnson could be the difference between a defeat and a drubbing.