When David Ifshin died at the age of 47 he had already lived more than one life. And if you want to understand the forthcoming US presidential election and how it can be won, you could do worse than listen to his story.

When, in 1996, cancer killed Ifshin so tragically young, Bill Clinton spoke at his funeral. Warmly and well, of course. The man was born to make such speeches. It wasn't a surprise that the President came and paid tribute. For Ifshin had been his general counsel in the 1992 campaign, as he had been for Walter Mondale in 1984. He had been a good Democrat, had Ifshin.

The other man who gave a eulogy, who broke down while delivering it, was altogether a more unlikely figure. It was John McCain. But it was not Senator McCain's party label that made his presence intriguing. It was his extraordinary history, and that of Ifshin.

When a young man David Ifshin had been a radical, really quite a radical. He hadn't contented himself with opposing the Vietnam War, he had done the unthinkable, for many the unforgivable. As president of the National Student Association in 1970, he went to Hanoi and urged American troops to turn against the Vietnam War. His remarks were broadcast over Radio Hanoi. And Radio Hanoi was broadcast in the prison cell of John McCain.

Times Archive, 1967: US aircraft keep up Hanoi bombing

One of the American pilots shot down yesterday was Lieutenant-Commander McCain

BACKGROUND

• Magnus Linklater: 1968: we made a difference

• Tom Stoppard: 1968: The year of the posturing rebel

• Obama says battle with McCain starts next week

• Is McCain too old for the White House?

Mr McCain had been taken prisoner by the North Vietnamese when his plane was shot down. He returned to his country a hero. He had been crippled by the crash, he had been tortured by his captors and yet, when offered early release to serve Vietnamese propaganda purposes, he had refused. How could he ever forgive a man like Ifshin?

And yet he did. The young radical Democrat never repented of his opposition to the Vietnam War, but he came to regret his broadcast bitterly. He came to understand his country's big heart, its generosity. And so one day, at a Washington event, Ifshin approached Mr McCain and asked to be allowed to apologise. Mr McCain decided to let him. And extraordinarily the two became friends, campaigners together for human rights in Vietnam. Said the senator: “I realised he had not been my enemy, but my countryman.” He added: “His friendship honoured me.”

A friend of mine was with John McCain when Ifshin's wife rang to say that he had died. The senator spoke to her, then told his office to hold any further calls. For an hour he sat and reminisced about the lives that he and the young radical had lived, and how their different paths had finally come together. And my friend realised that here was the key to Mr McCain's appeal. Not just his humanity, but his ability, alone among his contemporaries, to heal the wounds of the 1960s. If he is going to win the presidency, it is upon this ability that he will rely.

For I believe that the winner of the election, a contest that might be a squeaker, will be the candidate best able to escape the legacy of the Sixties. Every election since 1964 has replayed the arguments of that decade; this is the first that can go beyond it. And the winner will be the candidate who grasps this.

The conventional view of modern US politics is that it began with Ronald Reagan. More specifically, that it began with the actor's televised speech in support of Barry Goldwater's doomed presidential bid. The idea is that Goldwater invented the modern conservative message, and Reagan became the messenger. Between them, message and messenger swept all before them, crushing any liberals in their path.

A new book at present garnering rave reviews in the US, Nixonland by Rick Perlstein, sees things rather differently. It views the current Republican coalition as the creation not of Goldwater and Reagan, but of Richard Nixon. Nixonland tells the story of how that strange, resentful, angry man built a political movement in his own image.

His was the idea to unite those in the South, resentful of the successes of the civil rights movement, with the strivers and the straights and the patriots in the North, who abhorred the excesses of the Sixties, and who wanted order, not chaos. Together these people formed Nixon's “silent majority”. These groups remain at the heart of the Republican coalition.

It was fantastically successful. In 1964 there was a Democratic landslide, in 1972 a Republican one. Nixon's movement has served his party well since then. Mr McCain will be tempted to try to ride it to power. A negative campaign against Barack Obama, suggestions of cultural and economic chaos, strong hints that the Democrats are peaceniks and dropouts. Mr McCain can even do the explosions of anger.

This would be a tragic error, a waste of one perfectly good John McCain. This is a man who missed the most turbulent years of the 1960s while in jail. He can rise above it. He can be the generous, positive, honourable man who never forgot his experiences but was able to forgive Ifshin. That's the McCain that wowed the press when he ran in 2000. Many of the correspondents were anti-Vietnam protesters and they particuarly valued their engagement with the war hero.

Time moves on. As the conservative author David Frum never tires of pointing out, there is a limit to the number of elections that conservatives can win fighting the memory of hippy leaders and 1968 rioters on the streets of Chicago. Nixon's coalition is growing old and dying. Mr McCain needs to create a new one. He has to decide if he wants to.

He is not, however, the only candidate who needs to escape the 1960s. For if John McCain must avoid becoming Dick Nixon, Mr Obama must avoid becoming George McGovern, the man whom Nixon destroyed in 1972.

Since McGovern's defeat, there have been only two Democratic presidents. Both were southern Democrats, running on relatively conservative platforms. There hasn't been a victorious northern Democrat since JohnF. Kennedy and there hasn't been a successful candidate campaigning as an out-and-out liberal since... well, since ever. It is not just because he is African-American that the election of the Illinois senator would be a revolution in US politics.

Just as Mr Obama has brilliantly risen above America's race politics, so he must rise above the generational politics of the 1960s. He must avoid being seen as the leader of a ragtag army of dreamers and pacifists, of people who wish America was someplace else. As Nixonland makes graphically clear, the chaos and extremism of the Left in the 1960s was not just a figment of Nixon's imagination.

There is a good and bad McCain, a good and a bad Obama. This election can plumb the depths or reach to the sky. Who soars, wins.

daniel.finkelstein@thetimes.co.uk

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