Although direct contacts between campaigns and individuals are a central part of the process that encourages political participation, it is often argued that their effects extend beyond the initial contact via a secondary process of indirect mobilization. This paper puts that argument to the test by investigating possible connections between direct party contacts and political mobilization in social networks. The results show that the primary social consequence of party contacts is to alter the substance, but not the volume, of politically oriented conversations that occur in social networks. These conversations in turn increase the salience of the campaign in the electorate but have only a mild effect on levels of campaign involvement. Although political mobilization does influence social communication, its effect on political involvement is restricted to socially based forms of involvement under limited conditions.