Rupert Cornwell: Barack Obama has inspired a generation, but his toughest battles are yet to come

One hates to be a curmudgeon this brave June dawn, when everything seems possible, and the most dazzling new political talent America had seen in a generation has pulled off a quite astonishing triumph, against all the odds. Few of us present that glacial morning just 16 months ago in Springfield, Illinois, when Barack Obama formally tossed his hat into the presidential ring, seriously believed he would be where he is today.

It's not just that, after the most enthralling and exciting primary season in memory, he is the first African-American to win the nomination of a major party. He has drawn millions of new voters into the political process. Thanks to a canny strategy, brilliant organisation, and above all an astonishing ability to inspire, he has bested the Clinton double-act that has dominated the Democratic Party for the best part of two decades. Make no mistake, this was an upset for the ages. But Obama (and this is one of his great strengths) is also a realist. He knows full well that if the battle thus far has been tough, it's going to get even tougher. And others know it too.

Like it or not, on this brave June dawn, there's also a whiff of buyers' remorse in the air. The phenomenon is understandable enough. A protracted contest was always going to prompt some second thoughts among voters. Inevitably, it has exposed the flaws and weaknesses of every candidate.

The Obama of today is not the unsullied, Messiah-like figure who at one point reeled off a dozen straight wins against Hillary Clinton. He is visibly tired, he has made his share of gaffes. To be sure, his victory speech after the final primaries was the spell-binding Obama of old (a mixture of Martin Luther King and JFK, with a hint of Abraham Lincoln, enthused one CNN commentator on Tuesday night). But that oratorical pedigree could not disguise the fact that he has limped over the finish line, having won only six of the last 14 primaries. Small wonder Clinton finds it so hard to admit defeat. "Losing by a landslide is easy," a senior Democrat commented the other day, "what's tough is losing by a whisker."

Obama has been placed under scrutiny – albeit belatedly. Even so, with barely three years service in the Senate (and much of that spent on the campaign trail), he remains an unproven quality. In his duel with Clinton, he has shown a worrying inability to win the big swing states, especially the quartet of Ohio, Pennsylvania, Florida and Michigan, two of which at least Democrats must win to capture the White House, under whatever combination of electoral college arithmetic you choose.

Much has been made of Obama's appeal to Republicans and independent voters. The plain fact is that right now there are as many, if not more, "McCain-ocrats" – Democrats likely to cross over to John McCain – as there are "Obama-cans", especially among blue-collar whites in states like, yes, Ohio, Pennsylvania and Michigan.

At this opening moment of the general election campaign, Obama must be counted favourite to win in November. Indeed, no Democratic candidate worth his salt would not be. Republicans go into this election saddled with a lousy economy, an unpopular war, an even more unpopular incumbent President, and an unprecedented number of Americans who believe the country is heading in the wrong direction. Even so, McCain is within striking distance in the national polls.

The least of Obama's tasks is what to do about Hillary, introduced by her campaign chairman, Terry McAuliffe, as "the next president of the United States" hours after Obama had publicly secured more than enough to guarantee him the party's nomination, beyond even the obfuscatory powers of Clintonian semantics.

What the lady wants is a matter for speculation. Is it the vice-presidency, a special mandate to reform health care, or both, or something else entirely? One must presume, that despite her refusal in New York on Tuesday evening to so much as breathe the word "concede", she will quietly acknowledge defeat in the next few days. But you can't be sure. No wonder many Obama supporters fear that she (and/or Bill) has some last trick up her sleeve that would snatch the nomination away. My own guess is that they don't, it's just that the Clintons find it harder than most to admit defeat. Even so, the odds probably are that, at the end of the day, Obama will not put her on the ticket.

But assume that the Clinton issue is resolved, and that at a choreographed and triumphant convention Obama is proclaimed the nominee by acclamation, much as was Walter Mondale in 1984, after a battle with challenger Gary Hart that was almost as fierce and as close as the one this year. Even having re-united the party, the nominee still would be vulnerable.

There is, for one thing, his liberal record. The set-piece speeches to huge audiences at which he excels tend to be long on platitudinous idealism, but short on specifics. But if McCain is more conservative than he lets on, Obama is more liberal. Indeed, as Republicans gleefully point out, his voting record since 2005 is the most liberal in the Senate.

Already he is tacking to the centre. The flag pin, that emblem of "patriotism" once conspicuous by its absence from the Obama lapel, is once again in evidence. He now ends his speeches with a rousing "God Bless America". And tellingly, on the very morrow of his triumph, there he was at the AIPAC conference in Washington yesterday, proclaiming a presidential contender's obligatory fealty to the state of Israel. Yes America by its own standards is moving leftward. But is it ready for Obama's liberalism, especially when set against the military hero appeal of John McCain?

Even more fundamental, is America ready for a black president? This is the supreme unanswerable of a general election campaign that will be as fascinating as the Democratic primary contest that has just ended. The polls, eliciting only what people say, not what they think, are no guide. If America is not ready, then all of Obama's capacity to inspire, all his message of change, will count for nothing. If it is ready, then he will win, and maybe by a landslide.

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