The intensity of its involvement in the latter, varies from one system, and from one electoral level, to another. In the case of parliamentary elections, in some instances they hold the monopoly for the presentation of candidacies, whilst in nearly all of them the identification of the list on behalf of the party that backs it, is determinant. In presidential elections, the personality of the candidate is obviously significant, as well as which political party he belongs to. Special requirements for political parties can also be derived from the fact that some of their activities are subsidised with public funds. In some particularly advanced codes, mechanisms have also been created to ensure that their structure and functioning are democratic.
Parties can have very different structures.
The first parties reflect the structure of the earliest constitutions, with restricted votes and political participation limited to a small portion of the male adult population. These groups were relatively lax as far as their programmes and ideologies were concerned, in which personal connections and attachments were determinant. Initially, their fundamental mission was to try to assure their own re-election and subsequently assure the recruitment of new parliamentarians, in a political career whose first step in national politics was normally taking up office as a member of parliament. Their evolution has been radically different in the American and European continents, each one of which has exported their model to other areas under their political and cultural influence. The large or mass parties emerged in Europe in the second half of the nineteenth century with radically different features.