In the late summer of 2004 I sat down for dinner with a friend who was running the Republican Senate campaign in Illinois. He looked disconsolate. Things were not going well.

The Republicans hadn't had much luck with their candidate. Their first nominee had been forced to stand down when his wife accused him of taking her to sex clubs with a view to having sex in public. The man who succeeded him was a hardline Christian who declared that Jesus would not support a Democrat and attacked the Vice-President's lesbian daughter for being a “selfish hedonist”.

Strangely, however, that wasn't why my friend believed they were being routed. The real reason was that the Democratic candidate was brilliant, flawless, a rock star, a phenomenon. And that was when I first heard the name of Barack Obama, now President Elect.

One reading of this election is that it has been an ordinary contest transformed by an extraordinary candidate. America remains the same, runs this theory. It is still an innately conservative nation. The reason this election has been different - and has ended up with the victory of such an apparently unlikely man - is because of the talents and failings of the candidates involved.

This is not a theory I accept. This election has turned out as it did because it needed to. The emergence of Barack Obama only happened, only could have happened, because America is changing profoundly. This was not a landmark election because it featured exceptional candidates. It featured exceptional candidates because it was a landmark election.

Here's how America has changed:

The American people are becoming, literally, a different people.

The most obvious change exposed by this election is in attitudes to race. Little more than 40 years ago Barack Obama would have found it hard to be served lunch in a restaurant, let alone be US president.

In 1962 Alabama Democrats chose George Wallace as their candidate for governor and a few months later he was sworn in, standing on the gold star placed on the spot where, a century earlier, Jefferson Davis had been sworn in as President of the Confederate States of America. And Wallace had this to say: “I draw the line in the dust and toss the gauntlet before the feet of tyranny, and I say segregation now, segregation tomorrow, segregation for ever.”

Segregation did not last for ever. It did not even outlast George Wallace. And in 2008 Alabama Democrats chose Barack Obama for president.

The traditional politics of white America are being tranformed. The country is changing demographically, rapidly and visibly. US Census Bureau figures suggest that, by 2042, white Americans will be in a minority.

Karl Rove, George Bush's strategist, has long been convinced that the Republicans had to co-opt the Hispanic community or the party would suffer badly in future. That is one reason why, against the instincts of his party, Mr Bush supported a liberal policy on immigration, one that John McCain backed too.

America will never be the same again, because Americans won't be the same.

The world is changing and with it America's place in the world.

America remains the greatest single power in the world, yet the rise of China, the new belligerence of Russia and the wealth of the Gulf set this election in a very different context to its predecessors.

In this election America was not looking simply for a candidate able to command its forces as it enjoyed undisputed hegemony. It was more anxious than that. It was looking for a leader, like Mr Obama, who could command and might deserve the respect of the world.

The crisis in the financial markets only added to that feeling. For the first time in a generation the free market ideal and its advocates were on the back foot.

American politics is being captured by the rising middle class.

For 40 years American politics has been shaped by the split in the Democratic Party over civil rights. Richard Nixon's Southern Strategy, launched at the end of the 1960s, was to bring over to the Republicans disaffected voters from the segregationist states. It was almost completely successful.

Democratic presidents such as Franklin Roosevelt, Harry Truman and John Kennedy had united the liberal North with the poor and dispossessed whites of the deep South. After the Civil Rights Act this link was broken. And Democrats struggled without this source of southern support.

Yet slowly what one might term a mass chattering class has emerged to make a northern liberal candidate like Mr Obama viable as they had not been since Kennedy. A record number of Americans now complete high school or go to college. There are 7.3 million American millionaires, and more than half the country now considers itself middle class and is working less and enjoying more leisure time. Even to be competitive with these voters the Republicans had to select an unconventional candidate. And still he lost.

We have reached the end of the Southern Strategy and that changes American politics profoundly.

The conventional Republican agenda has stopped working.

The big themes of Republican politics - cut income tax, fight crime, reform social security, outlaw abortion, support marriage - no longer cut it politically. The Democrat tunes play better.

Tax cutting has lost its edge because 29 million Americans pay no income tax at all and because the Democrats have learnt how to blunt the message. Success has made crime less of a preoccupation. And the desperate need for Republicans to win votes among women makes their stance on abortion a serious problem.

The Republicans were forced to select a maverick because they did not have an electable mainstream Republican candidate. This was because the mainstream Republican agenda is no longer a winner.

Welcome to a new American president. Welcome to a new American politics.

daniel.finkelstein@thetimes.co.uk

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