Ezra points out this comment from Garance Franke-Ruta:
Now, I happen to think that, seven months before the election, there's a little too much attention paid to the day-to-day fluctuations in the polls -- especially with a candidate in the field like Kerry, who is a strong closer but tends to appear weaker than he is before the end of a race. Six weeks before Kerry's 1996 re-election, Republican Massachusetts Gov. William Weld was happily leading in the polls in his race for Kerry's senate seat, and former Vermont Gov. Howard Dean looked like a sure bet to win the Democratic nomination as close as one month before the 2004 Iowa caucuses. Nonetheless, the Bush campaign is working on a long-term project to undermine Kerry that could pay massive dividends later this year by framing Kerry now in such a way that whatever he does come autumn is viewed through the Bush campaign's narrative about him.
Meanwhile, Kerry's effort to define himself has been hampered by his lack of funds and by his need for a vacation. Kerry, as has been well-documented, has not thus far been the kind of candidate who has reached out and grabbed the nation with his powerful oratory, compelling personality, or innovative domestic agenda. But he has been viewed, at the very least, as a credible -- and sometimes even strong -- alternative to Bush by the Democratic party base and some percentage of swing voters. The upcoming election may well be defined in wholly negative terms -- that is, neither candidate can really win it, but one of them can be made to lose. Right now, it looks like Bush is winning the war to make Kerry lose, and winning it in the states that will matter.
This is similar to thoughts I have had that this race may come down to a question of which candidate least pisses off the electorate. I think that Karl Rove understands this dynamic and has decided that risking the damage to Bush's reputation as a good guy is worth the risk that comes from going negative hard and early against Kerry. The basic calculus is this: Bush's negatives are going up and are likely to continue to go up by November. So, the only way to win is to make Kerry's negatives go up higher and faster.
I just hope that the Kerry campaign understands that this is what is going on.