Abstract. This paper focuses on the floating vote and the floating voter at three critical junctures in modern Swedish political history: the general elections of 1928, 1948, and 1968. The topic is in the mainstream of electoral research, but with one important proviso: it is a study of floating without the benefit of survey data. The analysis is based on Thomsen's (1987) method of ecological inference. The ecological estimates confirm the conventional wisdom that the Swedish elections of 1928, 1948 and 1968 were mobilizing elections, bringing large numbers of new voters to the polls, and marked by considerable mobility between the parties. They were also realigning in that they held out the possibility of a new status quo. In 1928 and 1948 the parties of the right were on the offensive; in 1968 the Social Democrats held the initiative. But the new coalitions were potentially unstable; it was the floating voters, particularly those with a previous history of non‐voting, who spelled the difference between defeat and victory. The paper makes an important contribution to the validation of Thomsen's method. Copyright © 1991, Wiley Blackwell. All rights reserved
