It's going to get worse
I've talked before on this blog about how the general election campaign will run in three phases. The first phase was the "should we re-elect Bush" phase in which the voters asked themselves whether Bush deserved to be re-elected. This was the phase that ran roughly from when Kerry locked up the nomination to the Democratic convention (actually, I'd place its end on the day Kerry picked Edwards).
In my judgment, the voters are strongly leaning towards kicking Bush out. However, that judgment won't translate into a defeat for Bush unless Kerry makes the case that he would be a good replacement. That was the second phase, and it ran roughly from the DNC convention/Edwards pick up to about now.
The verdict for Kerry is a mixed bag. It was going good for him in the days before and after the DNC convention, but the Swift Boat issue derailed Kerry's "elect me" campaign and it has never fully recovered. Sadly, I don't think Kerry has made a compelling case to the voter that he would be a good alternative.
But the voters still aren't all that sure about Bush. So now we begin the third phase, running from now, through the debates, until election day. In this phase the voters will have to decide if their previous judgments about both Bush and Kerry are justified.
The electorate right now is so polarized that I have my doubts that, barring unforeseen circumstances, few of the Bush and Kerry supporters are likely to change their minds. Furthermore, the positive case for Kerry has been damaged enough that the only alternative left for him may be to run a negative campaign, ala Bush's against Kerry, from now until election day. Kerry has to convince the few remaining fence-sitters that pulling the lever for Bush will be more distasteful then pulling it for him.
Kerry's failure to hit it out of the park in phase two means that we can look "forward" to a campaign that is almost exclusively about each candidate's negative opinions of each other.
Whoever crosses the finish line is going to be bloodied.