Odd, incompetent, or what?

Here's a report of a reaction-test performed by a lab upon 300-plus Americans, using mouse-responses during quick intervals while watching McCain's negative "celebrity" ads about Obama. The lede of the report, which is accurate, states that among Republican viewers, after watching the ads, more reacted negatively toward McCain than reacted positively. The same is true of those viewers who deemed themselves "independent" voters. But what the article fails to state--a remarkable omission, due, probably, to incompetent reporting--is that among the one-third of the viewers who called themselves Democrats, the reaction to the ad was to increase McCain's "favorability," and by a margin similar to that by which McCain's favorability fell among Republicans after viewing the ad.

Does this mean that Democrats are dumber than Republicans and Independents? Or what?