Uruguay's party leaders were sometimes viewed as forming a "political class." Many of the surnames of those active in politics in the 1980s would have been familiar to Uruguayans a century earlier. Blanco leaders were more likely than Colorados to have attended private secondary schools and to describe themselves as practicing Catholics, although this distinction was breaking down. With the exception of an apparent increase in the late 1960s, these politicians only rarely had business careers, apart from ranchers in the National Party. Rather, most made their living as lawyers and as public servants.

The leaders of Uruguay's leftist parties were drawn from a somewhat wider spectrum of backgrounds than the Colorados and Blancos. Among the leaders of the former were many white-collar workers, especially educators, and a few labor union leaders.

The power of traditional political bosses, or caudillos, has resided in their ability to mobilize voters by means of patronage machines. This system of doling out favors, such as public-sector jobs and pensions, through local political clubs had, nevertheless, declined by 1990. Young voters were more motivated by ideology than their parents, which is one reason that the membership of Uruguay's leftist parties was growing, whereas that of the traditional National and Colorado parties was declining.

Data as of December 1990