I feel like the positive/negative question, if that was the wording, might be pushing people toward one side of the question.  Who wants to say that they are opposing something labeled as "positive"?  And, given the negative connotation of the term "attack ad," who wants to support attacking something?  

A better wording might have been presented as a choice between "offering an agenda for what policies they would enact if elected" versus "criticizing the record of Republicans in the White House and Congress"? I don't think it would make a difference in the direction the wind blows, but the numbers might change a bit.

I understand the desire to give people a forced choice between a dichotomy, but the first part of the survey makes me think that the netroots constituency believes that Democrats need to spend more time and effort on both offering an agenda and attacking the Republicans.

I would also have liked to see respondents offered a question on whether Democrats should run "moderate" candidates in districts where a "truly liberal or progressive" candidate may still have a reasonable yet clearly inferior chance of winning, rather than "little chance" (a moderate in a 50-50 tossup or a liberal with a 40% chance, for example), although I have no idea how I would phrase that.  I think that would have offered a better measure of how pragmatic the netroots really are.