If there was a clear winner of last night’s first presidential debate for the Republican presidential nomination, it was probably Ronald Reagan.

If there was a clear loser, it was probably George W Bush.

Neither, of course, is running for the party’s nomination in next year’s election. Mr Reagan has served his two terms and gone on to his eternal reward in the western sunset. Mr Bush is constitutionally barred from running again and will shortly be settling down to a more earthly retirement.

On the more important question, therefore, of which of the ten candidates actually running emerged as the winner, judgment will probably have to wait.

The ten stood in the shadow of Mr Reagan’s Air Force One on the grounds of the Reagan presidential library, and paid their fulsome dues to the party’s most popular leader in the last half century. Mr Reagan was mentioned 16 times in ninety minutes and his wife, Nancy, who hosted the debate and was in the audience, was also praised.

By contrast Mr Bush was mentioned by name not once, several of the candidates explicitly criticised the handling of the Iraq war, and most of them tried in different ways to distance themselves from the man who might be remembered as one of the party’s most unpopular leaders of modern times. .

This unusual lack of support for the incumbent president underscored the challenge Republicans face if they are to win next year’s presidential election. They have to persuade people that the Republican party – despite all that has happened in the last couple of years – is still the best equipped handle the thorny issues of war and domestic economic discontent. But they have to explain why they would be very different from Mr Bush.

Among the big three candidates, Rudolph Giuliani, John McCain and Mitt Romney, who have a clear advantage over the others in the early opinion polls, Mr Giuliani probably had the worst night.

He was especially unconvincing on the issue that most threatens his candidacy: abortion. The Republican primary voters tend to be more conservative than the population and predominantly anti-abortion. Mr Giuliani has long supported abortion rights. He has tried so far to square the circle by insisting that he is personally against abortion and that he would appoint judges who would strictly interpret the constitution, a usefully ambiguous code that suggests he might nominate justices to the Supreme Court who would be prepared to overturn Roe v Wade, the 1973 decision that found a constitutional right to abortion.

But he fumbled last night; on the Roe v Wade question he suggested he didn’t mind either way if it was overturned or not, and despite his carefully rehearsed position, he emphasised repeatedly that he thought women should be free to choose whether or not to have an abortion. That may play well with a general election audience, but with religious conservatives it could be very damaging.

After a slightly hesitant start John McCain came across as firm on the issue that most threatens his campaign – the war in Iraq.

The McCain campaign has clearly concluded to make his principal asset his national security credentials and so, rather than run away from his support of the war Mr McCain chose to emphasise how important it was to win it.

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