ON almost every step of his march towards the Republican nomination, John McCain has relied on the support of his glamorous second wife Cindy. Yet she has not always been a political asset. A Republican victory in November would bring to the White House a formidable but flawed first lady.

McCain’s marriage has long attracted attention both for the 18-year age gap between husband and wife and for their adopted Asian daughter, who became the focus of one of the most vicious dirty tricks of the 2000 presidential campaign.

The couple have also overcome daunting health problems that included McCain’s bouts with skin cancer, a stroke suffered by Cindy in 2004, and her admission a decade earlier that she had become so addicted to painkillers that she was stealing them from a medical charity she ran.

Yet somehow the McCains have emerged as a potent and durable political partnership. Cindy McCain was at her husband’s side last week as he celebrated the Florida primary victory that has put him at the front of the Republican field.

A former Arizona rodeo beauty queen and daughter of a millionaire Phoenix businessman, Cindy McCain was 25 when she met her future husband at a cocktail party in Hawaii. John McCain was a 43-year-old naval liaison officer travelling with a congressional delegation, his sights already set on a political career.

He was also still married to his first wife Carol, although the couple had recently separated. Carol later attributed the breakdown of the marriage to “John turning 40 and wanting to be 25 again”. McCain fell like a brick for Cindy, who was the heir to a brewery distribution business worth millions. For several years afterwards the McCains endured Washington gossip that he had dumped his first wife - who had been crippled in a car accident - in favour of a trophy bride to enhance his political ambitions.

It was in the late 1980s, after a series of miscarriages and giving birth to three children, that Cindy developed spinal problems and was prescribed painkillers after surgery. Her husband and family had no idea she was secretly taking pills stolen from a charity she had created called the American Voluntary Medical Team, which sent mobile surgical units to war zones. When federal agents began to investigate gaps in the charity’s records, Cindy telephoned her husband, a senator in Washington, and confessed.

She admitted at the time that the 1994 episode had “nearly destroyed both of us”. But she underwent treatment and attended meetings of Narcotics Anonymous as part of a deal with prosecutors who dropped charges.

A few years earlier she had visited Bangladesh with a different charity and decided on the spur of the moment to help a little girl with a cleft palate whom she met in Mother Teresa’s orphanage.

The McCains eventually adopted the girl, named her Bridget and raised her as their daughter. She is now 16, but during McCain’s ugly presidential primary fight against George W Bush in 2000, voters in South Carolina began receiving telephone calls suggesting the senator had fathered an illegitimate black child.

The authors of the smear have never been identified, but Bush was the beneficiary and went on to win the South Carolina primary and the Republican nomination. The McCains have never publicly blamed Bush and their relations have been outwardly cordial. But Cindy recently admitted that she keeps a “grudge list”.

Cindy McCain, now 53, claims she has no interest in policy making - “I am not the legislator in this family. He is” - and that she intends to keep busy running her charities and her family’s company. As first lady, it is clear that she would play a key role. Acknowledging that McCain had made many enemies in Republican ranks, she added: “The only person my husband can trust is me.”

Watch Cindy McCain on The Early Show

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