Erik Moberg ã:
A Theory of Democratic Politics
5.4 - PRESIDENTIALISM
Presidents can be appointed in popular elections in different ways. In essence, however, the whole country may, in a presidential election, be considered as one single-member constituency. The methods used are therefore usually variants of the plurality method or the double ballot method. When those methods are used there is, as we saw in part 5.1, and just considering the character of the method, no need for political parties at all, but still parties usually do play important roles.
In part 5.3 we saw that parliamentary systems depend, for their proper functioning, on cohesive and disciplined parties. With presidential systems it is the other way round. There stable, cohesive parties, rather, are a problem since since they may impede or block the proper decision-making. Such mechanisms will be further discussed when we come to the presidential systems in the following. The mechanisms, it should be noted, are observed by some political scientists. Sartori, for instance, remarks (1994, p 94, my italics) that in a presidential system "under conditions of divided government stalemate is avoided precisely by party indiscipline".