Do Mad Men's low ratings really matter? The satellite channel's top-rated show is the equally high-quality but lower-profile Game of Thrones, which returns on Monday for its second series. The fantasy epic pulls in a loyal 750,000 viewers - more than double what Mad Men was getting on BBC Four and now ten times as many. However, to a superficial media, its cast of dwarves and bearskin-clad bearded warriors aren't nearly as photogenic as square-jawed Jon Hamm or curvy Christine Hendricks. Neither does a medieval kingdom have the same snob value as 1960s New York. Mad Men allows pundits who might normally deem TV beneath them to wax lyrical about retro fashion, period furniture, civil rights, proto-feminism, cigarette smoke and three-Martini lunches, rather than admit they're reeled in by the sexy, soapy plots. Mad Men is simply one of those shows with miniscule ratings but massive cultural cachet. Like The Wire, The West Wing or The Killing, it appeals to a vocal minority. When Channel 4 screened the US remake of The Killing last summer, some complained that the publicity campaign didn't mention the Danish original. That's because under four per cent of the population had even heard of it, let alone watched it. A hardcore of noisily passionate fans, many of them in the media, proclaim The Wire as the best TV drama ever. However, few outside the chattering classes can be bothered with its bleak Baltimore setting, mumbled dialogue, arcane slang and long, difficult plot arcs. If you read broadsheet newspapers or upmarket magazines, you could be forgiven for thinking that these programmes are the biggest on television. In reality, they're insignificant minnows compared to the big two soaps (which draw 140 times more viewers than Mad Men) and a tiny speck of dust on Simon Cowell's stacked-heel shoe. Do low ratings really matter, though? Such shows aren't intended to appeal to everyone. Instead they're a benchmark of quality for the rest to aspire to. They will endure, stand up to repeated viewings, inspire analysis and discussion. They're the screen equivalent of a literary novel: read by a select few, yet still more culturally significant than most best-selling bonkbusters. Their style and standard of writing, acting and direction will filter down to more mainstream shows that pull in more viewers. They also perform a valuable function of raising the reputation of television, meaning the medium continues to attract the finest creative talent and isn't seen as a poor relation of film or theatre. The likes of Mad Men might not put bums on sofa cushions like Coronation Street or The X Factor, but those who do watch them love them. They also improve the medium as a whole. Don Draper would surely raise an Old Fashioned to that. Mad Men is on Sky Atlantic on Tuesdays at 9.00pm