THERE ought to be a watershed for party political broadcasts.

Just as minors should be protected from salty language and scenes of a sexual nature before 9pm, so the unsuspecting viewer would appreciate being shielded from politicians nakedly courting support before the curtains are closed.

David Cameron's five-minute audience with the public this week was the PPB stripped bare. No crowd scenes, no fanfare. It was the Prime Minister's "I'm a pretty straight sort of guy" moment (copyright T Blair). In this case, Mr Cameron advertised himself as the guy who got the job done. "You're not Prime Minister to be the good guy or the bad guy, to be the popular guy. You're there to be the guy that gets the job done."

In keeping with the simple style of the piece, Mr Cameron gazed slightly off camera, addressing an unseen presence. It might have been the Downing Street cat, roped into the role because it had not been quick enough off the mark after dinner. Or the PM could have been looking at portraits of those currently rumoured to be plotting to unseat him. It is a gallery that is growing by the day. If it gets any larger, they'll be adding a gift shop.

The fair lady among the portraits is one Theresa May, the Home Secretary. Such was the excitement that greeted her recent wide-ranging address to Tory activists, some in the party are said to be regarding Mrs T May as the new Mrs T, or Angela Merkel in kitten heels. She has the handbag(s) to be the new Mrs Thatcher. She has the moxie (one cannot imagine her turning down a televised debate with Alex Salmond). But does she have a Vienetta in Hades chance of turning her party's fortunes around?

Once best known for informing her party, while serving as its chairman, that people were calling them "the nasty party", Mrs May has come a long way from that 2002 conference in Bournemouth. Made a Secretary of State by Mr Cameron after the 2010 General Election, she has flown across a trio of hurdles that would have sent a lesser being sprawling.

First, she has survived working in the Home Office, the Bermuda Triangle of political careers. She has kept her job despite riots in English cities, her failure to get Abu Qatada on a plane to Jordan, and a falling out with the police. Second, she has made a non-issue out of being a child-free woman in a party, and a society, that still expects its womenfolk to do the traditional family thing. Lastly, she has dug her way out from beneath the mountains of piffle written about her clothes and shoes.

Ah, the shoes. Much was made of Mrs May telling off her party while wearing leopard-print kitten heels in a style labelled "Hot to Trot". The shoes are generally used in evidence if anyone accuses Mrs May of lacking personality. Ken Clarke's brown suede shoes have played a similar, if lesser, role. Both politicians appear happy with the deal.

The former Chancellor is not the titan from another era with whom Mrs May is usually compared. In highlighting her upbringing as a vicar's daughter, her allies would like potential supporters to think of a certain Grantham grocer's daughter of old, and contrast Mrs May's start in life with that of her wealthy-from-birth Cabinet colleagues. Her no-nonsense style, her retention of a feminine air in a man's world, her work rate – all the Pavlovian bells have been rung by those who think she could do just as good a job as Mrs Thatcher, or at the very least a better job than the incumbent.

For "better job" read "save our jobs". It is not just the Conservative rank and file who don't fancy the party's chances at the next UK election. A survey of more than 1800 members by the ConservativeHome website, published on the same day Mrs May made her speech to activists, showed that just 7% thought the party could win a majority. If those who stuff the envelopes and knock on doors are downbeat and in a mood to man the lifeboats, imagine what the average Conservative MP in a marginal seat must be feeling. Don't laugh.

Such hysteria can only account for the frankly barmy army way the party is behaving, talk of leadership contests and all. They cannot help themselves. From dinner party plotting to Boris Johnson, London mayor, keeping his options open when his term ends in 2016, it is like 1975 (Heath v Thatcher) all over again. Or 1989 (Meyer v Thatcher). Or 1990 (Thatcher v Heseltine). Or 1995 (Major v Redwood). The party has a lethal pash for leadership contests, an addiction to the mania.

Like mullet haircuts and shoulder pads, Tory leadership contests are things best left in the past. Voters detest them because they represent the worst sort of political selfishness, especially now, with a triple-dip recession looming, the cost of living soaring and wages stagnant. Tory MPs are not the only ones concerned about their jobs. Many would think themselves lucky to even have a job to be worried about.

That such manoeuvrings should be taking place on the eve of a crucial Budget is as tiresome as it is sickening. If Mrs May is the kind of canny politician she would have us believe she would be dampening down talk of a leadership bid. She may yet take this tack when she attends the Conservatives' spring forum in London tomorrow. Even then, her every sentence will be analysed for signs that she is keeping her options open. Such is the reputation that the Conservatives have acquired, such is the culture that has grown up around them, they cannot escape being thought of as the kind of nasty party that calls a leadership election when it suits them.

In a profile of Mrs May, one acquaintance from the old days spoke of how the young Theresa wanted to be the first female Prime Minister and was quite put out when Mrs Thatcher beat her to it. Mrs May had to settle instead for being the party's first female chairman. She booted the door down then, snazzy footwear and all, but the chances of her doing so again appear to be receding. The other contenders-in-waiting should join her in finding something better to do with their time. Whatever the high regard in which they hold themselves, Theresa, Boris and the rest should know that frankly, dears, the voters no longer give a damn.