Political change and stability of the popularity function: The French general election of 1981

France experienced in May, 1981, a drastic political change, the influence of which on stability of the popularity function, from V. Giscard d'Estaing to F. Mitterrand, is examined here. First, a survey of existing estimates of French popularity functions is presented, and the main problems they raise are briefly discussed. The theoretical effects of government change are then analyzed, with a distinction between global effects (honeymoon and others) and distribution effects; these effects are then linked to the moves of ideologically motivated voters. Finally, new estimates are presented on French data for two periods, the first corresponding to Giscard's tenure only and the second including Mitterrand's tenure. The main conclusion is that the popularity function remained fairly stable, except for a move in the intercept when the Socialists came to power. This move is, in large part, the result of attitudinal changes in the more ideologically oriented electors, as results on disaggregated data indirectly confirm.