There is a new conventional wisdom in the American presidential campaign. It is that it is now John McCain’s to lose. The argument is that the infighting among the Democrats – the damage done to Hillary Clinton by her tactical shamelessness and to Barack Obama by his connections to black liberation theology – is a boon to McCain.

The Republicans have selected their best possible nominee for November, while the Democrats’ best two still haven’t resolved their death match, which could continue for months. McCain’s favourability ratings are at 67%, an eight-year high. In the national poll match-ups, McCain has pulled even with Obama and Clinton.

On last week’s nostalgia tour, he seemed his usual ebullient self. He has earned the punchy poise of a man who has seen some of the lowest lows one can imagine in life and some of the highest highs. History has treated him well – who now would have picked George W Bush over McCain in 2000, given what we now know?

His most recent foreign policy speech was an elegant and important statement of a new American engagement with the world. Europeans – and Britons, especially – should know that they have a Republican nominee who still believes in America’s indispensable role in leading the civilised world but has also absorbed the terrible price of arrogant unilater-alism. Here he is on March 26: “We need to listen to the views and respect the collective will of our democratic allies. When we believe international action is necessary, whether military, economic or diplomatic, we will try to persuade our friends that we are right. But we, in return, must be willing to be persuaded by them.”

McCain understands that he cannot and should not win this election as the third term of Bush. He is a fiercely combative person, a military man to his core, and a Teddy Roose-velt Republican of the impetuous, romantic variety. But he is also a realist and understands perhaps better than any other leading Republican the damage that the past seven years have done to the reputation and power of the United States.

He saw quickly that the Donald Rumsfeld-led occupation of Iraq was a slowly unfolding catastrophe of mismanagement and negligence; almost alone in the Senate, he grasped that something had gone horribly wrong with the White House’s moral compass in its authorisation of torture and interrogation methods that had once been inflicted on him by enemies. More, he cannot ever countenance what he thinks of as military defeat or surrender, but he was also able to oppose, as far back as 1983, the intervention by Ronald Reagan’s administration in the Middle East: “I do not foresee obtainable objectives in Leba-non. I believe the longer we stay, the more difficult it will be to leave, and I am prepared to accept the consequences of our withdrawal.”

Americans also feel they know him, flaws and all, and trust him as a decent, honest man by political standards. Are his age and health insuperable burdens? He would be 76 at the end of his first term (and is not Hollywood enough to dye his hair like Reagan). He was once literally broken by torturers and is in recovery from a melanoma that has scarred his face. The late-night comedians have been making the Grandpa Simpson jokes for a while now. But the actual truth is: you have to be around him for only a few minutes to be in awe of his prodigious energy, his seeming inability to be tired, his zest for life and fun and friendship. Having watched both of them in action, I would say that Obama is more easily tired than McCain.

For all this, I’d argue that the conventional wisdom about McCain’s soaring chances this autumn is unsound. It’s not his age. On some core grounds, his struggle is inherently uphill.

His fundraising remains anaemic. In November he is likely to face Obama, a candidate who has a staggering 1.3m individual donors. In the first three months of this year he raised $131m. McCain has not released his March fundraising numbers but he raised a sad $23m in January and February combined. Obama raised almost twice that much in March alone.

The Bush machine has yet to embrace McCain and vice versa. And the religious right cannot and will not muster much enthusiasm for him. He simply isn’t one of them and once accused some of being “agents of intolerance”. He is pro-life and opposed to civil marriage for gay couples, but he is not animated by these issues.

His enmeshment with the Mesopo-tamian occupation and his near-fatal offhand remarks that he could “bomb Iran” and stay in Iraq for “100 years” if necessary are obvious liabilities in a country exhausted by the apparently fruitless militarism of two gruelling counterinsurgency campaigns. It looks as if it will be hard for him to run as the architect of a “successful” surge in Iraq, as the sheer complexity of the many wars and wars within wars that are now simmering across Iraq sinks slowly in.

In short, it’s hard to see how the US surge of troops in Iraq helps him in November, whatever happens. If troops cannot be withdrawn for fear of all-out civil war, if violence is back up after a lull, the surge may appear as digging a deeper ditch for America to get out of. McCain will seem like Bush, the Sequel. If, on the other hand, Iraq has calmed, the risk of a young, inexperienced bridge-builder such as Obama may seem less serious.

It’s lose-lose for McCain. If another serious attack hits the mainland, or if a miracle happens in Iraq, he may still have a chance. But he is a war candidate; that’s his brand. And war is currently deeply unpopular.

The polls, moreover, show the economy emerging as the major issue of the campaign. Even McCain admits he is uninterested in economics. He admirably rejects the easy impulse to use taxpayers’ money to bail out the reckless lenders and borrowers of the real-estate bubble. But this is not exactly popular in the distressed heartland. And Obama has been slowly learning how to address these issues.

On two critical narratives, an Obama-McCain match-up is tough for McCain. One voted against an unpopular war; the other supported both the invasion and the surge. One will be 72; the other will be 47. The narrative will not be age as such; it will be the future versus the past. Americans are future-oriented people – and this election so far has disproved the usual truth that the next generation does not vote. If Obama is the nominee, there will be a tsunami of a youth and black vote, the likes of which America has not seen since the 1960s.

It is also simply a fact that in times of war and economic recession the incumbent presidential party has a hard time winning reelection. The Republicans have been wise to nominate the least Republican of their candidates. But the odds are still high that a Democrat will win. That’s why Clinton won’t bow out. She knows in some ways that this spring may be more decisive in selecting the next president than this autumn. McCain knows this too. But he also knows from his long career that anything can happen. That’s Clinton’s only hope. In the long term in this campaign it’s also McCain’s.

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