The NY Times shows that voters should beware of polls that show Republicans way above Democrats because when the matchup is given by name, the individual Democrats do much better…
Republicans did better on the first set of questions, which asked voters whether in general they would prefer to see a Democrat or a Republican elected in the district. On average, over the 31 districts, Republicans led on this question by 6 points: 39 to 33.
When the candidates were named, however, the Democrats’ gap was lessened. They trailed by an average margin of 2 points, 43 to 45. (Results from the individual districts that American Action Forum tested are shown below.) That might imply that the generic ballot overestimates Republicans’ standing by about 4 points, at least in swing districts.