The study was conducted under the supervision of Warren Miller and Donald Stokes. An attempt was made to interview 151 incumbent congressmen, their opponents, and any third candidates that were associated with the 1958 congressional elections. Interviews were obtained from 251 candidates (weighted to 1,364). The questions were designed to elicit information on what the candidates considered to be the most important issues and what their positions on these issues were, what the candidates felt the position of their constituents to be, what things the candidates felt influenced them, and what things they felt influenced the outcome of the campaign. Information from this survey is organized in three data files. The first is a candidate file which has 11 cards of data for each candidate and 365 variables. This same information is also contained in the two candidate and constituent files but is organized so that the district is the unit of analysis rather than the candidate. One of these files is organized by party identification of the candidates. The second is organized by incumbency status of the candidates. In addition to the survey information on the candidates, the candidate and constituent files contain information on constituents taken from 1956, 1958, and 1960 American election studies.