Researches on "party migration" are relatively recent in our country, although the literature often points to this phenomenon as another sign of non-institutionalization of our party system. Some experts analyzing the theme have tended to point to the non-restrictive legislation as the main cause of those migrations. This article argues that it is not the absence of restraint, but the gains to be obtained with the move the factor explaining the "party migration" in Brazil.
party migration; party system; electoral system; non-paid electoral propaganda