You know the drill by now. America is a schizoid country, split between red and blue, divided into traditional families and countercultural radicals. The Republicans represent the old school, the Democrats the postSixties libertines.

It’s a helpful stereotype — “I’m in Kansas, they must all hate gays” — but like all stereotypes, it doesn’t quite fit reality. In Kansas many people don’t hate gays; many Kansans are gay; and even the antigay ones can be really nice, especially when you’re lost and need directions. And there are some flaming lefties I know whose mouths go dry and whose knees wobble at the thought of going into a gay bar.

But you see the inadequacy of the rubric most clearly in the presidential race. Look at the Democrats. Of the three frontrunners all have intact, lifelong marriages, with children. If they were Republicans the religious right would love them.

Barack Obama has been married for 15 years and has two daughters; Hillary Clinton . . . well, whatever you say about her she has stuck with her cheating husband for years while he has continued to humiliate her. John Edwards is perhaps the most admirable of them all. He has been married for 30 years to Elizabeth, a remarkable and accomplished woman. They have had five children, but their 16-year-old son was killed in a car accident in 1996.

Most couples never survive the death of a child. The Edwards family did — and went on to have two more, Emma Claire and Jack. The latter is now seven years old.

All three Democrats speak candidly about religious faith. They hail from Hawaii, Illinois and South Carolina respectively. So much for the clichés.

Now take a look at the party of “traditional values” and the religious right. Republican warhorse John McCain’s first wife Carol stayed loyal to her husband during the Vietnam war when he was abroad, imprisoned and tortured. She also, however, had a car accident, put on weight and needed crutches to get around.

On his return McCain did not stay faithful, met another woman, Cindy, and divorced his first wife. His children are a diverse group: he adopted two kids from his first wife’s first marriage, has a daughter with his first wife, has three children with his second wife, and adopted a seventh from an orphanage in Bangladesh. His first wife still loves him, his second wife adores him and his Brady Bunch-style family has apparently worked out fine. But it’s a little complicated, contemporary and has a pale shade of blue.

Rudy Giuliani is a New Yorker and his family life reads like an episode of Sex and the City. He has three wives under his belt, several rather public affairs, a nasty break-up with his second wife Donna Hanover and is somewhat estranged from his son.

He informed his second wife that he was divorcing her and marrying Judith Nathan at a press conference. It wasn’t the first time he had embarrassed her. “I had hoped that we could keep this marriage together,” his second wife once said. “For several years it was difficult to participate in Rudy’s public life because of his relationship with one staff member.” She was referring to Giuliani’s relationship with yet another woman.

Giuliani’s website doesn’t mention his children or his former wives. Not much of this has yet sunk in with Republican primary voters now ranking him as their favourite. We’ll see what happens when it does.

Newt Gingrich married his first wife Jackie when he was 19. She was loyal, faithful and helped put him through graduate school. He still dumped her later on and had the class to file for divorce while she was in hospital recovering from cancer surgery. LH Carter, his former campaign treasurer, recalls Gingrich saying of Jackie: “She’s not young enough or pretty enough to be the wife of the president. And besides, she has cancer.” He refused to pay alimony or child support.

His second marriage lasted almost two decades, but it broke up while he was having an affair with a staffer 23 years younger than him, to whom he is now married. He was having the affair while coordinating impeachment proceedings against President Clinton. He recently confessed to James Dobson, a leader of the religious right, that: “There were times when I was praying and when I felt I was doing things that were wrong. But I was still doing them . . . I look back on those as periods of weakness and periods that I’m . . . not proud of.” I’m not judging any of these men. We are all human and we all fall short of our own standards. But the sharp discrepancy between the party of “family values” and the actual messy, complicated lives that many leading Republicans have led makes for some unmissable ironies. Political liberals are often quite conservative in their private and family lives; and many political conservatives have chequered or lively pasts. The contrast between moral Bushites and immoral Clintonites is a distorting one.

The Republicans do have one clear squeaky-clean candidate. He’s Mitt Romney, who married his high-school sweetheart and has five sons with the fantastically wholesome names of Tagg, Matt, Josh, Ben and Craig. The boys have so far produced 10 grandchildren. If Romney gets the nomination, the convention family scene will look like an outtake from the Osmonds.

But that, of course, is the problem. Romney is a Mormon, and his family values are not rooted in evangelical Christianity or even Roman Catholicism. For the faithful Republican base, their hero stands athwart a slightly troubling pedestal.

My own view is that none of this matters much. Unless you have someone with a pathological sex addiction like the last president, most American leaders’ private lives don’t affect their political judgment. Sadly the crude way in which Republicans targeted Bill Clinton for sexual misbehaviour and in which Karl Rove appealed to evangelical voters through the biography of George W Bush made the personal more political.

What we’re seeing now is an adjustment back to a better balance. The Republican base has been forced to recall that a leader matters not because of his private foibles and indiscretions, but because of the policies he supports and the character of his public conduct.

Republicans once understood this before the polarised age of Bush and Clinton. Their icon Ronald Reagan was, after all, a divorced man who almost never went to church. And in the messy details of McCain’s, Giuliani’s and Gingrich’s lives, Republicans are mercifully relearning that the morality card can backfire if played too crudely.

Maybe they’ll be a little less reluctant to rush to judgment in future. That’s progress, it seems to me, and a little more grown up and humane. Heaven knows, of course, if it will last.

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