Sex stereotypes are ubiquitous (Ashmore, Del Boca and Wohlers, 1986; Broverman et al., 1972; Williams and Best, 1990), and lead people to perceive men as possessing agentic traits such as boldness and aggressiveness, while women are perceived as possessing communal traits such as warmth and sympathy (McKee and Sheriffs, 1957, 1958; Parsons and Bales, 1955). In the context of modern political campaigns, where negative campaigning is on the rise (e.g., Mayer, 1996; Johnson-Cartee and Copeland, 1991; Ansolabehere and Iyengar, 1995), and is often viewed as an effective strategy (see Finkel and Geer, 1998; Kahn and Kenney, 1999; Freedman and Goldstein, 1999; Brians and Wattenberg, 1996), examining how stereotypes influence the impact of negative campaigning is an important question. To examine this question, a content analysis will be conducted to examine gender differences in the reliance on negative advertisements in congressional campaigns, using 1998 and 2000 data from the Wisconsin Advertising Project and the Campaign Media Analysis Group (CMAG). To examine differences in the effectiveness of negative campaigns for men and women candidates, an innovative experiment will be implemented. Political commercials will be created and shown to subjects in an experimental setting; and four factors will be varied in the commercials: (1) the gender of the sponsor of the ad; (2) the tone of the ad; (3) the gender of the target of the ad; and (4) the content of the ad, creating a 2 (tone) x 2 (sponsor gender) x 2 (target gender) x 4 (content) factorial design. By only varying the independent variables of interest, and by keeping all other content the same in each of the commercials, the differences in subjects. evaluations of the candidates can be attributed to the variation in the independent variables. Finally, an examination on whether the subjects. political and demographic background (e.g., political party, race, gender) condition the impact that stereotypes have on their reaction to negative campaigning will be examined. The intellectual merit of the dissertation project is that first, it builds on the psychological literature that examines gender stereotypes by revising ideas about the substance, pervasiveness, and consequences of gender stereotypes. Second, it builds on the political science and communication literature that examines negative campaigning by improving scholars understanding of the effectiveness of different types of political messages for different political candidates. The broader impacts resulting from the project include a deeper understanding of how effective negative campaigns are for women congressional candidates. Since research shows that women politicians often expand the legislative agenda (Clark, 1998; Dodson, 1998; Mandel and Dodson, 1992; Thomas, 1994; Thomas and Welch, 1991), and are successful at addressing issues that get short shrift by male officeholders (e.g., women and children.s issues) (Dodson et al., 1995; Dodson 1995; Schreiber 1995; Witt, Paget, and Matthews, 1994), increasing the number of women in elective office is an important goal in our representative democracy. Therefore, it is necessary to explore the obstacles women face when running for office. In this study, by examining how gender stereotypes influence the impact of negative campaigns, women.s likelihood of increasing their electoral presence will be examined.