First Night: Trevor McDonald meets David Cameron, ITV 1

SamCam unleashed on Sir Trevor in first act of election battle

Airbrushed or not, David Cameron's face looks a bit like a stress ball. If you gave it a squeeze, however forcefully, it would probably just spring back into shape, as fresh and boyish as ever. The same seems to be true of Cameron himself when interviewed; however hard you press him, he regains composure almost instantly. Unlike Gordon Brown, he has well and truly mastered the art of the Blair chuckle: lob a tough question at him, and he simply laughs it off.

Hopefully, before the election, some interrogator will grip the Conservative leader strongly enough to wring out a few awkward grimaces. But that might have to wait for the televised debates. Andrew Rawnsley gallantly gave it a go last week in Cameron Uncovered on Channel 4, but without conspicuous success. Alan Titchmarsh certainly didn't manage it, and nor indeed did Sir Trevor McDonald last night. In fact, the most significant admission the veteran interviewer extracted from his subject was that he's posh.

Cameron's fellow posho, posh Giles Andreae, lately of Eton College and the dead posh Bullingdon Club, gamely defended his friend from accusations of excessive poshness. But come on, Giles – he was wearing a suit at home! Only posh people do that, surely? I suppose we'll have to take Giles's word for it that they didn't spend their entire time at Oxford quaffing champagne in tails; Cameron did get a first, after all, so he's not posh and stupid.

Of course, the show wasn't really about Sir Trevor McDonald meeting David Cameron at all; it was about ITV viewers getting a good look at his wife. Electoral spin is now practised so openly that we know McDonald's programme was the first of eight "high-profile" events in which SamCam will participate prior to polling day. This was electioneering masquerading as meta-electioneering: Sir Trevor asked Cameron how he planned to "deploy" Samantha during the campaign, without even acknowledging that she was being deployed there and then.

Conservative Central Office had obviously furnished their first lady with a list of approved adjectives for use when discussing her husband ("strong", "funny", "clever", "supportive"), to which she dutifully adhered. Yet she hesitated momentarily before first referring to him as "Dave", and then – as if to rectify her blunder – found excuses to say "Dave" again three times in quick succession. When you ask a political wife to list their husband's flaws, they always come up with incredibly limp stuff. "Dave", apparently, is messy (but only when cooking – ladies, he cooks) and he rewatches The Godfather Parts I to III incessantly (that's right lads, he loves a good DVD boxset). *Yawn*.

Turns out Samantha isn't super-posh like Dave. She calls dinner "supper", but she's more Emma Thompson posh than Princess Anne posh. And she does seem awfully nice. So does Dave, actually. And his mum. But before we get carried away cooing over the Cameron family album, let's not forget what this programme was really about. It opened and closed with footage of Cameron running. Running ... now, might that be a metaphor for an election? "People want to know what the Conservative Party is about," Dave insisted. Still, he wasn't about to tell us just yet. In fact, I'm pretty sure I didn't hear a whisper of policy all evening. But hey, that's showbiz.