Obamamania sweeps Britain. So many primaries are being held in the American presidential contest that we thought the 51st state should not be left out. So Populus asked British voters which of the two Democrat challengers they preferred, and then, separately, to choose between either of the two Democrats and the Republican Senator John McCain.

The results are fascinating at several levels. First, and most obviously, Senator Barack Obama has caught the imagination of the British public across the board. He is both known and seen as fresh and exciting. Nearly a half of all voters (48 per cent), and the same proportion of men and women, and of Labour and Tory voters, prefer Senator Obama.

Hillary Clinton has won the backing of 35 per cent of the British public, with no difference between men and women. She receives most support among Labour voters, at 41 per cent, and least, 27 per cent, among Liberal Democrats, who are the keenest on Senator Obama, at 66 per cent. Only 17 per cent do not express an opinion either way.

Secondly, more than a half of British voters want to see a Democrat win in November. Senator McCain gains the support of a fifth or less of the public. Senator Clinton would win by 56 to 20 per cent, and Senator Obama by a virtually identical 54 to 19 per cent. Of course, the two Democrats have been in the news a lot more recently, though Senator McCain is one of the best-known American politicians in Britain.

Conservative voters are the most enthusiastic about Senator McCain, with about a quarter supporting him. But this is roughly half the number backing either of the two Democrats (24 to 54 per cent in a McCain/Clinton match-up and 26 to 48 per cent in a McCain/Obama one among Tories). The precise figures have to be treated with caution since the numbers answering the second question are relatively small. But the trends are clear cut.

Labour voters back either of the Democrats by huge margins against Senator McCain (67 to 14 per cent if Senator Clinton is the nominee and 64 to 11 per cent if it is Senator Obama).

Senator McCain is probably being tarnished by a strongly anti-Republican mood among British voters, fuelled by the unpopularity of President Bush and the Iraq war. Back in September 2004, Populus asked whether British voters preferred President Bush or Senator John Kerry to win the presidential election that November. The Democrat came out ahead by 52 to 29 per cent. And for all the talk of a neoconservative alliance, Tory voters backed Senator Kerry over President Bush by 50 to 35 per cent.

The poll shows the extent of transatlantic disillusionment after the Bush era, and, by implication, the potential for rebuilding of relations after the new president takes office next January. The trouble with Obamamania, however, is the risk of excessive expectations, and consequent disillusionment when/if American policies change less than hoped.

.— Populus interviewed 757 adults by telephone between May 2 and 4 on the Clinton versus Obama question, and 544 of these people between May 6 and 7 on a recall question about the choice of president. For more details, go to www.populus.co.uk .

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