WHY THE DEMOCRAT-REPUBLICAN PARTISANSHIP GAP VARIES FROM POLL TO POLL

Polls taken in late 1980 and 1984 varied by up to 20 pointsin the spread they reported between Democratic and Republicanidentifiers. We found three systematic and sizable differencesacross polls: polls that sample only voters, polls that emphasize"today" or the present in their question wording, and pollsthat are taken close to election day (at least in circumstanceslike those of 1984) tend to favor the party currently advantagedin the presidential race.     

QUESTION WORDING AND PUBLIC SUPPORT FOR CONTRA AID, 1983-1986

How does question wording affect the results of polls? How canwe distinguish question wording effects from genuine change?In this analysis, we make use of a series of polls concerningPresident Reagan's policy toward Nicaragua. We identify fivevariations in wording in the survey items that have been usedon this topic, and we find evidence that these are responsiblefor variations in support for the Contras. If the ideologicalnature of the Sandinistas, President Reagan, the amount of moneyto be spent, and/or the role of the Contras are mentioned, orif a balanced question format is employed, the poll resultscan be substantially affected. Once these factors are controlledfor, we can argue that there was a small but statistically significantincrease in support for Reagan's policy over the period 1983–1986.