Making a Difference? Exposure to Political Ads and Perceptions of Parties

How effective are candidate, party, and interest group ads at conveying noticeable differences between the Democratic and Republican Parties? Or at boosting preferences for the parties? There are two conflicting expectations; first, that ads from these three sponsors will have the same effect on citizen perceptions, under the assumption that viewers do not notice sponsorship. The second expectation is that party ads have a stronger effect on perceived party differences (that is, at “building the party image”) than candidate and group ads. There have been very few empirical investigations into these common claims, however. I leverage a comprehensive dataset that tracks political ads in the nation’s top media markets on surveys of U.S. voters in 2000 and 2004. The results demonstrate that sponsorship does matter, but not in ways that confirm the second expectation. When ads convey party distinctions, the effect comes from candidate ads (and to a lesser extent, from interest group ads); to that effect, party-sponsored ads almost never matter.