The tribal assembly of the Romans is a classical example, but the centuriate
assembly is a good one, though more mixed in nature, as it was controlled by the oligarchs to a large extent.
(1) Under these circumstances, as described by Cicero in his rhetorical treatise Brutus and supplemented from other sources, where appropriate, we can distinguish two groups of orators at contiones, that is, at informal popular assemblies (2) took place usually before an official vote at a centuriate or tribal assembly, which were the main official assemblies of all Roman citizens (comitia centuriata or comitia tributa): (3) one that undermined the res publica and one that supported it.
Yakobson (1992), "Petitio et Largitio: Popular Participation in the Centuriate Assembly of the Late Republic," Journal of Roman Studies 82, 32-52.
Ultimate electoral sovereignty under the Roman system sprang from two electoral assemblies: the Comitia Centuriata and the Comitia Tributa (hereafter referred to as the Centuriate and the Tribute, respectively).
The Centuriate functioned as a Roman electoral college; it met each year to elect the chief magistrates, including the consuls and proconsuls (governors).
Flaccus passed the necessary law in the centuriate
assembly and was appointed by Sulla as his Master of Horse.
(69) Aerarii, citizens excluded from the centuriate
and tribal organization by the censors and subject to the payment of a special poll tax, that is, lowest class citizens.
Particularly insightful is William McCuaig's examination of Augustin's memorandum on the Roman Republican reform of the centuriate
Likewise, the competitiveness of the men whom the tribal and especially the centuriate
assemblies elected to magistracies made casting lots the only practical way of enabling them to divide their duties, particularly the provinciae.
To look at the most important of the assemblies, the centuriate
assembly, this operated on a system of group voting in which the richer you were, the fewer voters were placed in the group in which you voted and therefore the more valuable became your vote.