The Christchurch By-Election: Scale of defeat sets Tory alarm bells ringing: Lib Dem victory cannot be dismissed as a one-day wonder, writes Ivor Crewe

WAS THE Christchurch result another 24-hour 'sensation' or a milestone on the Government's road to defeat?

By-election history is full of Liberal false dawns and mid- term protests that evaporate at general elections. The Conservatives lost seven by-elections in the last Parliament, usually on large swings. But they won the general election, recapturing all seven seats, four of them within a year of the by-election. Why should Christchurch signify anything different? Can't the Government breathe a quiet sigh of relief that it was the Liberal Democrat and not the Labour vote that went up and simply wait for the slow recovery in the economy to translate itself into votes? Not entirely. Three features of the results are a warning against gov ernment comp lacency. The first is the sheer scale of the Conservatives' defeat. Christchurch goes off the Richter Scale of by-election earthquakes. Commentators' references to the 'biggest swing against the Conservatives since the war' fall short of its true measure.

It was the largest swing against any government since Britain's modern party system was established in 1918. Setting aside freak results caused by party splits, no modern government has seen its support fall by as much as the Conservative vote fell in Christchurch.

On Thursday the Conservative vote fell by 32 percentage points, three points more than in Newbury three months ago. Half of Christchurch's Conservatives in the 1992 general election abandoned their party on Thursday. Earlier mid-term by- election protests against Conservative governments pale in comparison: a modest 22.4 in Orpington in 1962; 26.4 in Sutton, in the dog days of the Heath government, 22.4 in Ribble Valley in 1991 at the peak of public opposition to the poll tax. Labour supporters are traditionally less loyal than Conservatives, but no Labour administration has suffered as much as John Major's government. After devaluation in 1967 the widely despised Harold Wilson and his Labour government lost hitherto impregnable seats such as Walthamstow West, Dudley and Oldham West to the Conservatives and Hamilton to the SNP. But the most its vote slumped was 30 points in Hamilton, and that figure was inflated by the fact that the SNP had not contested the seat in the general election.

After the 1976 run on sterling and intervention by the IMF, the Callaghan government was utterly discredited in voters' eyes, but the worst by-election drop in the Labour vote was 28 per cent in Walsall North in November 1976.

Secondly, the recession is not the whole explanation. For one thing, Christchurch is relatively recession-proof: its prosperous or retired voters are largely unaffected by bankruptcies and unemployment and complain that interest rates are too low, not too high.

More important, personal economic optimism (the 'feel good' factor) is not unusually low. In the last quarter's Gallup polls it has averaged minus six, not nearly as adverse as its double digit level for most of 1989 and 1990, when the current recession began, or in 1981 during the Thatcher government's first recession. Yet this relatively moderate level of economic pessimism has been accompanied by unprecedented disillusion with the Government, whether expressed in this year's local elections and by- elections, or in historically low poll ratings for John Major and his record. Public malaise with the Government reflects more than economic woes. Voters 'feel bad' not just about the economy but about the Government itself.

Thirdly, Labour's derisory vote (2.7 per cent) confirms the new pattern of ruthless tactical voting first seen at Newbury (and foreshadowed by the Conservatives' minuscule 2.9 per cent in Liverpool Walton in 1991). In comparable by-elections in the early and mid- 1980s, third-placed Labour candidates generally held their vote, but since the 1987 general election the Labour vote in Conservative-Liberal Democrat contests has been squeezed progressively hard.

Recent Mori polls of the South-west and of rural seats suggest that since the general election the Liberal Democrats have won over tactical Labour support as well as Conservative protesters. Labour can afford to be genuinely cheerful about being squeezed by the Liberal Democrats. It merely means that they do badly where they cannot win anyway, and can continue to put up candidates without seriously splitting the non-Conservative votes. But it spells danger to the Tories in the 20 or so seats in the South where the Liberal Democrats are the challengers and there remains a sizeable third-place Labour vote.

The Conservatives will recapture Christchurch at the general election. The Liberal Democrats' massive victory probably signifies no more than a modest advance of 10-20 gains from the Conservatives at the next election. But that could well determine which of the two Johns becomes prime minister.

Ivor Crewe is Professor of Government at the University of Essex.