This research compares the impact of two advertising tactics, humor versus fear appeals, while considering the moderating effects of two characteristics of the source, attractiveness and communication habits. A set of hypothesis is proposed and tested using a between-subject experiment, in the context of the 2007 French presidential election. Results show a moderating effect of source attractiveness on attitude toward the ad. Humor should be favored over fear when the message targets undecided voters or supporters whereas fear should be favored when the message targets opponents. Perceived communication habits - perceived previous use of the advertising tactic by the candidate - also moderate message effectiveness such as humor is more effective when it is seldom used by the candidate, whereas fear is more effective when it is used on a regular basis.
