PARIS -- When Lionel Jospin was appointed prime minister of France in June 1997, there were not many people willing to bet on his longevity in office. The "plural left" majority on which he had to rely looked too divided on most issues, from Europe to immigration, to enable him -- or so it seemed at first -- to come up with solutions to the worrying economic situation he had inherited. He also lacked the broad electoral basis without which no government can survive for long: In many French constituencies, the left had won only because the extreme-right National Front put the left's candidate on the second ballot in order to outflank its archenemy, the traditional right. The rupture between NF leader Jean-Marie le Pen and his first deputy, Bruno Megret, however, has changed this picture.

Why is it then that the left has not only stayed high in the polls for months now, but is likely to be still in power when, in just over two years time, presidential and general elections are held? How has it happened that, despite the continuing popularity of President Jacques Chirac, who appears determined to run again, most forecasters think he could very well be defeated by Jospin, if the latter decides to run himself (as seems likely)? There are several explanations:

* The improved economic situation: Unemployment is steadily dropping, sales are booming in many fields, from cars to cellular phones, and housing prices are jumping. Stocks are reaching unprecedented levels. The result is a large increase in revenue, making it possible to seriously reduce the budget deficit and the public debt. Polls show that the French are more optimistic today than they have been in years. Of course, credit for this recovery goes first of all to the persisting U.S. wave of prosperity, and most European countries present the same picture. But when things go better, it's usual to give credit for it to the government of the moment, even if, in France as in the United States, it would be only fair to admit that the drastic steps taken by its predecessors have contributed as much to present growth as its own decisions.