Our recent telephone survey of 2,000 likely voters across 14 battleground districts shows that mailings to inform voters in a relatively neutral way about where the candidates stand on key issues have the potential both to increase support for Democratic candidates and increase the enthusiasm of Democratic voters.
In drawing the sample for this research, we systematically excluded respondents who are most likely to be strong Democrats (modeled partisan scores of 90 or higher), but we included strong Republicans. In the interviews, respondents heard how the candidates in their districts differ on 14 issues (see appendix). Among the full sample, support for the Democratic candidate increased by a net of 13 points. Among an apples-to-apples version of the sample (which also excludes respondents who are most likely to be strong Republicans), support for the Democratic candidate increases by a similar net margin of 14 points.