Jon Hamm on living in the shadow of Don Draper

If you're a Mad Men fan, Hamm is everything you'd hope for. Today, he's dressed in a cream suit, a blue-and-white striped shirt and tan brogues, and could easily have stepped off the set to slip into the seat next to me. This dapper apparel is all for the benefit of meeting the media, he assures me. "When I'm left to my own devices," he says, "I revert very much to my jeans-and-T-shirt days of yore."

Yet you feel he's compelled to present himself as an ambassador for the show that rescued him from being just another jobbing actor.

In person, he's as smart as Don and clearly doesn't suffer fools gladly. He was recently quoted in one magazine ranting about contemporary celebrities: "Whether it's Paris Hilton, Kim Kardashian or whoever, stupidity is certainly celebrated. Being a f****** idiot is a valuable commodity in this culture because you're rewarded significantly."

For her part, socialite Kardashian wrote on Twitter: "Calling somebody who runs their own business, is part of a successful TV show, produces, writes, designs and creates, 'stupid' is, in my opinion, careless." Ouch.

Just as handsome in the flesh (that steel jawline would have made him an ideal candidate to play Superman in his younger days), 41-year-old Hamm speaks with that same rich cadence that has seen his Mad Men character woo so many potential clients on the show. And he knows the effect he has. "You never get used to any of that," he admits. "It all feels ridiculous and crazy because, in my mind, I'm the same person I was since I was this goofy little kid from St Louis, Missouri."

But herein lies the Hamm dilemma: with the fifth season of Mad Men drawing to a close (it's been renewed for a sixth), the actor knows he must stretch himself beyond it. "Nobody wants to play the same role for their entire career – even a role that is as fulfilling as Don Draper," he says. "After the first or second season I got 40 scripts that all took place in the sixties or were all advertising guys – some iteration of Don Draper. And it becomes tremendously uninteresting if you are banging on the same piano key."

From hosting US comedy show Saturday Night Live to an Emmy-nominated guest spot on 30 Rock, Hamm has been in high demand. And of course a movie career beckons, although so far his roles have been limited to supporting parts slotted around his Mad Men schedule. In Howl, he played the lawyer in the obscenity trial surrounding Allen Ginsberg's poem; in Ben Affleck's bank robber drama, The Town, he was a gun-toting FBI agent; and in Zack Snyder's fantasy Sucker Punch, he was a lobotomy-performing doctor reimagined as a high-stakes gambler (don't ask).

However, Hamm's latest film, Friends With Kids, is different. A witty thirtysomething comedy-drama, it's a mite more personal than most movies. It's written and directed by Jennifer Westfeldt, his real-life partner for the past 14 years. Playing a small role in the film, Hamm also acts as producer for the couple's fledgling outfit, Point West Pictures. While most actors tend to have production companies simply to massage their inflated egos, hands-on Hamm is all about getting involved with the nuts and bolts of movie-making.

"So much independent filmmaking is trying to get through the insanity, whether it's raising money, getting around agents, managers or lawyers or just getting people to read the script," he says. "Nobody's making any money. You can't throw money at them and say, 'Do this, it's a million dollars! Knock yourself out!' You just have to say, 'Hey, remember that time we did that thing? Wouldn't it be fun if we made a movie together?' And when you're friends with people, because you happened to work with them before or you've got friends in common, all of that serves to make it much easier."

That's why you'll find Friends With Kids features a host of actors who appeared in Bridesmaids, last summer's hit girly movie, in which Hamm played a small role as the caddish lover of Kristen Wiig, the film's writer and star. Wiig repaid the favour by coming on board Westfeldt's film, alongside fellow Bridesmaids alumni Maya Rudolph and Chris O'Dowd. But while Bridesmaids was about those who get left behind in the race to get married, Friends With Kids deals with the next stage: what happens when your mates start, well, mating.

In the film, Westfeldt and Adam Scott play single friends who watch aghast as two couples in their social circle (Hamm and Wiig; O'Dowd and Rudolph) swap nights out for nappy-changing. All-too aware of the detrimental effect parenthood can have on a relationship – but both desperate to have children – they decide to have a baby together, but remain platonic friends.

Hamm's character may be a supporting player, but he snags the film's stand-out scene when he explodes at his wife in front of their friends during dinner. Reminiscent of the coiled anger that Don Draper holds just beneath the surface, it's proof of what a powerful performer Hamm can be – even in a comedy. Inevitably, though, the question turns to how close this tale is to his own life.

"It's not autobiographical," he says. "There is certainly some sort of personal relationship to it. But it's not our life story at all. We do have a lot of things in common with it."

Whatever he says, it's all too tempting to draw comparisons with Hamm and his off-screen partner. "Jon and I don't have children," the statuesque Westfeldt notes when we meet later. "We have a dog that feels like a child sometimes. We've certainly watched our closest friends all have children in the past four or five years, and it's a very funny thing that happens when you watch them move on to that stage of life, and you're not really a part of it. You're a little bit out of sync with your peer group. And I think there's the envy of: 'Is there this incredible life experience that we're missing?'"

In Hollywood terms, their relationship is unusual. Together for a decade and a half, they're child free and unmarried – and it clearly works. "I can be so laidback I tend to fall asleep and she can be so hypercritical that she can't," says Hamm.

"So I think we balance each other out in that respect and that's what has contributed to our longevity. We are also very honest with one another. We're very, very upfront. We don't try to hide anything from one another. It's kind of an adult way of dealing with things, I suppose."

If anything has put Hamm off marriage, it's his own upbringing. Raised in St Louis, where his father, Daniel, ran a trucking company and his mother, Deborah, worked as a secretary, his parents divorced when he was two. Remaining with his mother in Missouri, where she encouraged him to try his hand at everything from learning the violin to creative writing, Hamm was an active, alert child. But, when he was 10, his mother was diagnosed with abdominal cancer and died. Hamm moved into his grandmother's house, living with his father, who had two daughters from a previous marriage.

When he was 18, he left home for the University of Texas – only to be blindsided when his father passed away a year later. Without either parent "it was like I had no mooring", he says. Fortunately, he was not alone. "I had very good friends whose parents helped raise me. My best friend's parents sort of became my de facto parents over the years and I still consider them that way. I'm still very close to the friends that I grew up with and their families."

Returning to finish his studies at the University of Missouri, he worked in a daycare centre to pay the bills while becoming more involved in the college theatre department. While in high school, he'd performed the lead in a production of Godspell, and by the time he graduated with a degree in English he came full circle, returning to his old school to teach drama. He must have been good: students included his Bridesmaids co-star Ellie Kemper (better known as Erin the receptionist in the US version of The Office).

But Hamm wanted more. In 1995, he packed everything up, made his way to Los Angeles and stayed with his aunt and uncle initially. Later moving into a house with four other would-be actors, he scratched out a living waiting tables, while driving to auditions in an old Volkswagen he shared with one of his housemates. The vehicle was so beaten up it didn't have a roof. "It doesn't rain much in LA, but when it did, it was utterly miserable."

Hamm had given himself five years to succeed, although that proved ambitious. By 2000, he'd only managed a bit part (as Young Pilot No 2) in Clint Eastwood's astronaut adventure, Space Cowboys, and was broke.

"I've been very fortunate in the past few years to make a lot of money," he says, "and it really is paying for the five or six years where I would literally fill out my tax return and think, 'Wow, that is not a lot of money I made this year – I made $2000! I wonder how I ate?' I worked in restaurants – that's how."

Still, at least he had a partner in poverty. He met Westfeldt at a friend's birthday party in 1997, when both were total unknowns. She was auditioning for Jake Kasden's film Zero Effect and Hamm volunteered to help her learn her scenes (she didn't get the role).

But it was only after a year of friendship that they began dating. Meanwhile, Hamm featured on stage in Westfeldt's play Lipschtick (and the resulting 2001 spin-off movie, Kissing Jessica Stein). Other roles included a recurring one on cop show, The Division, alongside a small part in Mel Gibson's war movie, We Were Soldiers.

In truth, though, Hamm was just like all the other jobbing actors in LA, on a perpetual cycle of hope and disappointment. "I remember early on when he would be frustrated and not getting work," says Westfeldt. "I don't think anyone knew what to do with him at 25. It makes sense. And also because his success is long overdue, it's also more appreciated. It's probably a better time for it to happen for him, and for us as a couple – to have weathered the storms. We've both had ups and downs in our careers and we've been there by each other's side. So it's about time. It's exciting."

Famously, it took Hamm seven auditions to secure the role of Don Draper (Mad Men creator Matthew Weiner initially felt he was too handsome). Beating 80 other hopefuls, the relief washed over him. "You have these things called overnight successes. In my case, my overnight was 10 or 12 years of trying to work and become successful." Even then, Hamm and his co-stars had no idea this pilot would get picked up or take off.

Does he have any idea why the show has become so successful?

"I could go on about it for an hour if you want," he says with a smile. "I think people find a vicarious thrill in living in a different time, one that represented for many people a better time. Ironically, it wasn't better at all. If you were white, wealthy and male, it was awesome. If you were not in any of those categories, it was not. I think that's the myth the show tries to explode.

"The fact it's set in this tremendously stylish, intellectual and volatile time, not only in American culture but in the world, only serves to add to the ironic, dramatic and cultural impact, to the resonance of the landscape."

As much as Mad Men has become a cultural phenomenon (and Hamm a style icon), it hasn't been all plain sailing. Yes, he's won a Golden Globe and been nominated for an Emmy four times, but this time last year the show was in flux while Weiner and cable network AMC were in contractual wrangles. "The industry is terrifying," says Hamm. "I don't think anybody ever gets used to the industry. You can have a 100-year-long career and I don't think you'll ever understand it. It is, by its nature, multifaceted, duplicitous, crazy – you're in one minute, you're out the next. So I think the healthiest way to manage that is to try not to manage it."

It's why Friends With Kids might prove a vital turning point in his career. Since producing it, he's become a regular producer on Mad Men (he also directed one episode) – suggesting that he wants more than being just an actor for hire. He wants control, something the success of playing Don Draper has given him. "It's certainly made it a lot easier to get your phone calls returned," he says. You might compare his rise to George Clooney, who went from television bit-part player to ER star to matinee idol to respected producer-director. "There are certainly worse people to model your career after," Hamm concedes.

For the moment, he's taking baby steps, rather than breaking into big-scale movie production like Clooney. He's to return to the small screen with A Young Doctor's Notebook, a television adaptation of several short stories by Russian author Mikhail Bulgakov. Commissioned by Sky Arts, in association with Hamm and Westfeldt's company, the mini-series sees Hamm join forces with Daniel Radcliffe, who will play the same character but younger ("I'm immensely flattered by the thought I might one day turn into Jon Hamm," the young Harry Potter star recently told me).

In Hamm's eyes, it's all about "making your own opportunities and trying to do the things you want to do". After so long in the wilderness, he'd be a fool to simply drift from job to job. Instead, he and Westfeldt are creating a little empire (a surrogate, you might think, for children).

"I'm very fortunate," says the actor, "to live with an incredibly creative human being who seizes on ideas and then explodes them into scripts, and tends to not rest until they've come to fruition." No wonder he's so smitten with her. n

Friends With Kids (15) opens on June 29.