NED LAMONT, the winner of the Democratic primary for the Senate in Connecticut, is a lucky man. He has both old and new money; his great-grandfather was a partner in J. P. Morgan’s bank when it was still the most powerful private bank in the world. He has made fortunes in asset management and communications. In his filing, he states modestly that his net worth is between $50 million (£28 million) and $300 million. He was able to outspend Joseph Lieberman, the incumbent senator.

Mr Lamont lives in Greenwich, Connecticut, which is the end of the line for New York commuter wealth. If one takes the old New York, Newhaven and Hertford line from Grand Central, one passes through a series of smallish towns — New Rochelle, Mamaroneck, Harrison, Rye — which are on a rising scale of affluence and prestige.

Greenwich is the first town across the Connecticut border, and it always appealed to those who preferred to pay Connecticut rather than New York taxes. A millionaire who lives in Greenwich is a millionaire who has really made it. Ned Lamont did not need to make it; the old money in his family is about as posh as old American money gets, unless you happen to be a Mellon or a Rockefeller.

His victory over Senator Lieberman has upset the calculations of American politics, extending right to the top, and to all the potential candidates for the Presidency in 2008. Mr Lamont waged a left-wing, or, in American terms, liberal campaign. It was not quite a single-issue campaign because he talked about liberal domestic issues as well, including the demand for a universal health service, but he had a dominant issue. That was his call for the withdrawal of US troops from Iraq. Senator Lieberman had always been a defender of President Bush’s Iraq policy. He voted for the war, as did many other Democrats, including Senator Clinton.

However, Mr Lieberman has been much keener than most other Democrats to defend the actual conduct of the war, which most Americans now think to have been incompetent. Hillary Clinton has recently called for the resignation of Donald Rumsfeld, the Secretary for Defence. Senator Clinton’s political antenna are more sensitive than Senator Lieberman’s. Most Americans have lost confidence in the way the Iraq war has been run.

Some Republicans have reacted with satisfaction to Senator Lieberman’s defeat. Dick Cheney, the Vice-President, observed that it would encourage al-Qaeda, and there is some validity in that argument. Al-Qaeda has long believed that the United States is a paper tiger, lacking the will to persist in the face of Islamic terrorism. Mr Lamont had the support of countless bloggers who have taken a line similar to the anti-Vietnam peace movement of the late 1960s.

Mr Cheney has made his own mistakes, but he is not stupid. Mr Lamont was indeed the candidate of the peace movement inside the Democratic Party. He may have won by only a 4 per cent margin, but he did win. Some voters will suspect that the Democrats have gone soft on Iraq and perhaps on national security as well.

One can see the difficulty for Mrs Clinton’s strategy. Richard Nixon once pointed out that Republicans have to track to the right to win the primaries and then back to the centre to win the presidential election itself. The converse is true for Democrats. Can Senator Clinton track to the left, after the Connecticut primary, without falling off the edge of public confidence? There is, however, a weakness in this argument. Whose policy was Mr Lieberman defending? Whose policy was Mr Lamont attacking? The President’s. It is quite true to say that Senator Lieberman is unpopular, but he is unpopular because among Democrats he is the keenest supporter of the Bush policy.

Senators with three terms behind them are not often defeated by neophytes in primaries. If Senator Lieberman had been running on his own record he would almost certainly have won, even though he is a bit of a bore. He was running on Mr Bush’s record and he lost. When one does a cross check on the President’s own popularity, a poll last Friday showed an approval rating of only 33 per cent.

This leaves the Republicans, as well as the Democrats, in a quandary. Is the public mood shifting? Will the public, as with Senator McGovern in the 1972 election, turn against the Democrats as weak on national security? Alternatively, are they angry about the mistakes made in the Iraq campaign; have they, perhaps, turned against all incumbents? If the weight of Mr Bush’s unpopularity was too great for Mr Lieberman to carry, will it also sink the Republican candidate in 2008? Will it perhaps sink the Republicans in this November’s mid-term elections for Congress?

There is one potential Republican candidate who can neither be criticised for his record on security, nor for any failure to criticise weaknesses in the Bush policy when he thought the President was mistaken. That candidate is Senator John McCain, a genuine war hero and a man of independent mind. The 2008 election will be won by the party that has the support of the largest number of independent voters, to whom Senator McCain is particularly attractive.

In Connecticut itself a Rasmussen Poll reports that Mr McCain, along with one other Republican, Rudolph Giuliani, would beat Mrs Clinton. Connecticut would normally be expected to be a Democratic state in a Presidential election. Senator McCain was strong enough to survive torture in Vietnam; he has shown the essential quality of determination under extreme stress.

America will not vote for any candidate who shows weakness on foreign policy, but Americans are not content with the outcomes of the Bush Administration. The Republicans can win again in 2008 but only with a new look as well as a new leader.

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