McCain likes to illustrate his moral fibre by referring to his five years as a prisoner-of-war in Vietnam. And to demonstrate his commitment to family values, the 71-year-old former US Navy pilot pays warm tribute to his beautiful blonde wife, Cindy, with whom he has four children.
But there is another Mrs McCain who casts a ghostly shadow over the Senator's presidential campaign. She is seldom seen and rarely written about, despite being mother to McCain's three eldest children.
And yet, had events turned out differently, it would be she, rather than Cindy, who would be vying to be First Lady. She is McCain's first wife, Carol, who was a famous beauty and a successful swimwear model when they married in 1965.
She was the woman McCain dreamed of during his long incarceration and torture in Vietnam's infamous 'Hanoi Hilton' prison and the woman who faithfully stayed at home looking after the children and waiting anxiously for news.
But when McCain returned to America in 1973 to a fanfare of publicity and a handshake from Richard Nixon, he discovered his wife had been disfigured in a terrible car crash three years earlier. Her car had skidded on icy roads into a telegraph pole on Christmas Eve, 1969. Her pelvis and one arm were shattered by the impact and she suffered massive internal injuries.
When Carol was discharged from hospital after six months of life-saving surgery, the prognosis was bleak. In order to save her legs, surgeons
had been forced to cut away huge sections of shattered bone, taking with it her tall, willowy figure. She was confined to a wheelchair and was forced to use a catheter.
Through sheer hard work, Carol learned to walk again. But when John McCain came home from Vietnam, she had gained a lot of weight and bore little resemblance to her old self.
Today, she stands at just 5ft4in and still walks awkwardly, with a pronounced limp. Her body is held together by screws and metal plates and, at 70, her face is worn by wrinkles that speak of decades of silent suffering.
For nearly 30 years, Carol has maintained a dignified silence about the accident, McCain and their divorce. But last week at the bungalow where she now lives at Virginia Beach, a faded seaside resort 200 miles south of Washington, she told The Mail on Sunday how McCain divorced her in 1980 and married Cindy, 18 years his junior and the heir to an Arizona brewing fortune, just one month later.
Carol insists she remains on good terms with her ex-husband, who agreed as part of their divorce settlement to pay her medical costs for life. 'I have no bitterness,'
she says. 'My accident is well recorded. I had 23 operations, I am five inches shorter than I used to be and I was in hospital for six months. It was just awful, but it wasn't the reason for my divorce.
'My marriage ended because John McCain didn't want to be 40, he wanted to be 25. You know that happens...it just does.'
Some of McCain's acquaintances are less forgiving, however. They portray the politician as a self-centred womaniser who effectively abandoned his crippled wife to 'play the field'. They accuse him of finally settling on Cindy, a former rodeo beauty queen, for financial reasons.