One other interesting tidbit from that WaPo poll: According to the poll results, voters increasingly view Obama as a strong leader, and McCain slightly less so. Only 40 percent of voters saw Obama that way back in March, versus 51 for McCain. In May it was 42 for Obama, 46 for McCain, and today they're both viewed that way by 46 percent of voters.
Meanwhile, the poll write-up notes that, "among those who prize a candidate who would provide a steady, experienced hand, just 10 percent back Obama, down from 27 percent a month ago."
Now, these aren't comparable universes of people (the first reflects all respondents, the second just the subset of respondents who say they prize steadiness and experience), so there isn't necessarily a connection between the two numbers. But if, as these numbers suggest, Obama is losing people who value experience even as more people think he's a strong leader, it's interesting to speculate why that's happening. My guess is that Obama gets points for taking on McCain directly, which makes him look strong, even as the McCain campaign lands some blows here and there, which make him look inexperienced.