Rupert Cornwell: Curse this sheer dumb Republican luck!

In my wallet is a chit for a $100 bet I took out last summer with a Republican friend that a Democrat would win the US Presidency in November. These days I peruse the chit with the equanimity of a Bear Stearns hedge fund manager watching the sub-prime mortgage market go up in smoke.

Normally, I'm not a betting man. But like many, many others, I thought that what with an unpopular war, a wobbly economy, and a blundering incumbent, the Republicans didn't have a prayer. And today? The Iraq war is even more unpopular, the economy is heading for recession if it's not in one already, and George Bush now has the lowest approval rating – 28 per cent – of any president in 70 years. But after Tuesday's Democratic primary in Pennsylvania, I probably couldn't find even a credit default swap to cover my wager.

In part, it's sheer dumb Republican luck. They were the ones, you will remember, who were supposed to be facing a chaotic nomination struggle while the Democrats settled quickly and painlessly on a candidate (one Hillary Clinton). Instead, the opposite has happened. The Democrats are saddled with their longest, most divisive and most expensive primary fight ever. The Republicans meanwhile, largely by fluke, have come up with the one candidate who offers a decent shot at victory, in about as hostile a political environment for the party as you could imagine.

When I took out my bet, John McCain's campaign was dead in the water. But thanks at least as much to the blunders of his rivals and a split in the traditional conservative vote as to his own appeal and resilience, he wrapped up the nomination two months ago. He now has the luxury of watching his two adversaries exposing each other's flaws – picking at raw wounds in the Democratic body politic that, had matters gone as expected, would never have been opened in the first place.

Hillary Clinton's solid win in Pennsylvania means her battle with Barack Obama will continue, at least for the next fortnight, probably until the end of the primary season, and possibly all the way to the party convention in Denver. And rightly so. After months of being given a free ride by a fawning media, Obama is finally being tested. He had a rough ride during a televised debate last week, prompting his defenders to complain how trivial, nasty and unfair American politics had become (and now they tell us!). More to the point, Obama has learnt that platitudinous saintliness, however uplifting, is not enough on its own.

His remarks at a plush San Francisco fundraiser, about how poor white voters were "clinging" to God and guns out of their "bitterness" at how economic good times had passed them by, may or may not have contributed to his 10-point defeat on Tuesday. The "gaffe" illustrated the tendency to the supercilious and condescending that is one of his least appealing qualities. But it also must have brought home to this comparative political novice the old truth that, in politics, a gaffe is when you inadvertently blurt out the truth.

Either way, however, his defects are being exposed – and far better now, you might say, when there is still time to correct them, than in the general election. As the Clinton camp points out, if Obama thinks things are getting trivial, nasty and unfair now, then wait until the Republicans get after him in the autumn. In the meantime, if I were one of the Democratic "superdelegates" – the 800-odd party dignitaries whose uncommitted and independently cast votes will decide the nomination – I would be having kittens right now.

Yes, barring almost unimaginable disaster, Obama will have won the most states, the most delegates and a majority of the Democratic popular vote by the time the primary season winds up on 3 June. These facts will weigh heavily, and rightly so, on the minds of superdelegates as they make up their minds. You do not lightly cast aside the will of Democratic rank-and-file voters, as expressed in the ballot box.

It also happens to be a fact, however, that if the Democratic nominating system had awarded delegates on a winner-take-all basis (as is the case both in the Republican primaries and, via the mechanism of electoral college votes, in the general election), then Hillary Clinton, not Barack Obama, would now be in the lead. Even under the proportional Democratic system, however, Obama has had his chances to put it away. He failed to do so.

The first opportunity came early on in New Hampshire, where Clinton pulled out an upset win when defeat would surely have doomed her after her third place finish in Iowa. He had another chance last month in the primaries in Texas and Ohio (I ignore the bizarre Texas caucuses, whose results took almost as long as Zimbabwe's to emerge, but which Obama in the end won). A victory in either primary would have wrapped up the contest. Instead he lost both. And now Pennsylvania, where the result is uncannily – and for superdelegates, troublingly – similar to Ohio next door.

The pair have exposed the biggest chink in Obama's armour. For all his successes in small and medium-sized states, for all his unprecedented ability to galvanise young voters and black voters, he seems unable to win the big swing states that a Democrat needs to win the White House. And what about Michigan and Florida, stripped of their delegates after they defied party rules and advanced their primaries to January? Like Ohio and Pennsylvania, both are swing states, key to a Democratic majority in the electoral college (witness Florida 2000). Clinton won the primaries in both, albeit in Michigan by default.

Ah, you will argue, that Obama lost them in a closed Democratic primary to Clinton does not mean he will necessarily lose them to John McCain in November. But by the same token, Obama's victories in primaries and caucuses in a host of southern, Plains and Rocky Mountain states are equally insignificant. Most will stay firmly Republican in November.

What isn't insignificant however is the central weakness to his candidacy exposed by Pennsylvania and Ohio: his inability to attract white, blue-collar voters – the "Reagan Democrats" of yesteryear, whose defection in 1980 from Jimmy Carter paved the way for a generation of Republican political dominance.

This was supposed to be a watershed election akin to 1980, ushering in a new Democratic era. Now Obama, assuming he wins the Democratic nomination, may lose the Reagan Democrats all over again. Maybe it's because they see him as elitist. Maybe it's because he's black. Either way, who better to scoop up their votes than a straight-talking, white and all-American war hero called John McCain? Is it any wonder I tremble for my bet?

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