Kerry's own goal?

I've never paid so much attention to this issue before but the political athmosphere prior to the Nov 7 election in the US is really getting me interested.
I said to someone the other day, although the Democrats are likely to win big time for the Congress in this election, a lot could still happen before that day.
And guess what... It turns out to be true. Kerry's statement yesterday about the American kids sent to Iraq seems to be a big advantage to the Republicans. Kerry said (well, not literally) that the kids sent to the battle in Iraq are not the smart ones. I have no idea how it is an advantage for them but a lot of media believe so.
Anyway, let's just wait and see what happens next.