Heather du Plessis-Allan: Simon Bridges in the last chance saloon

COMMENT: Can you imagine Simon Bridges as Prime Minister? That earnest way he answers questions. His always-furrowed brow. His pleading eyes.

It's like he's begging you to take him seriously. It's like he's learnt his lines.

That's the look of a politician trying to imitate something he doesn't have. Authenticity.

Bridges never quite felt right for the leadership. It's that lack of authenticity, the baggage of the last government, the public obsession with his diction. But, there was always the chance Bridges would grow into the role.

Fat chance. Bridges is close to blowing it. His time is almost up.

That might sound harsh. After all, he's only been in the job seven-and-a-half months.

But he should've made it work by now. This should've been the easiest ride for an Opposition leader. The Coalition Government's been scoring own-goals from day one.

National didn't have to do anything to look better by contrast. Bridges could've turned on the telly, put up his feet, watched rugby for two-and-a-half years and still done better than he has.

Maybe it's a surprise to Bridges that things have spun so out of control so fast this week. One minute he was announcing Parliamentary leave for his MP Jami-Lee Ross. Nek minnit we're all openly speculating whether Bridges himself is toast.

If that takes Bridges by surprise then he's too naive to be in the job. Politicians don't live or die by the stuff-ups thrown their way. It's how they deal with them.

And all the way, Bridges' judgment over the leak of his travel expenses has been WTF-bad. This could've been a three-day story back in August. Instead, he's dragged into a two-month circus of speculation and intrigue.

Take this week, for example. Bridges knew Ross was one of the MPs widely rumoured to have leaked the travel expenses. He knew Ross' leave would raise questions about the original leak all over again. Yet, he held a press conference, defended Ross and used the word "embarrassing" to describe Ross' condition. Bad move.

Leaks work like this. First, someone leaks. Then, the leader gets the wobbles, makes mistakes and looks weak. Then, the leaker or another opportunist strikes again and again until the leader finally falls off his bike completely.

And this is exactly how this leak has played out. First the leak in August. Then Bridges made the mistake of ordering an inquiry. Then, behind the scenes, over the past few weeks, there have been leaks and rumours from within National. That's the reason Ross was one of the leak suspects. Because someone else leaked his name.

Bridges should've known this was likely. He's been in Parliament almost 10 years.

Bridges' shortcomings are adding up. Bad personal polling. Ordering the inquiry. Calling Housing New Zealand tenants meth crooks. Failing to impress business. In this week's Herald Mood of the Boardroom survey, Bridges scores almost as badly as Iain Lees-Galloway and that's the guy trying to torpedo business with employment law changes that terrify them.

Bridges feels like a placeholder leader. The party clearly hasn't dealt with the John Key break-up so they've picked someone who reminds them of Key.

Which might explain the lack of authenticity. Maybe Bridges is trying to emulate Key. But he can't. He hasn't got the political judgement.

We can see that. And clearly, so can someone - or many someones - in National. Which is why Bridges' days seem numbered.

To rescue this, Bridges must do a couple of things at least. First, kill off this leak story ASAP. Which probably means finding the leaker and making an example of them.

Then, make it possible for voters to imagine him as Prime Minister.

• Heather du Plessis-Allan is on Newstalk ZB in Wellington, weekdays, 8.30am-noon.