Democrats aren't the only voters disenchanted with Bush. So are many independents and Republicans, including those that voted for him last time around:

In dozens of random interviews around the country, independents and Republicans who said they voted for Mr. Bush in 2000 say they intend to vote for the Democratic presidential candidate this year. Some polls are beginning to bolster the idea of those kind of stirrings among Republicans and independents.

This one interviewee summed it up pretty good:

In the 2000 presidential election, Bill Flanagan a semiretired newspaper worker, happily voted for George W. Bush. But now, shaking his head, he vows, "Never again. The combination of lies and boys coming home in body bags is just too awful," Mr. Flanagan said, drinking coffee and reading newspapers at the local mall. "I could vote for Kerry. I could vote for any Democrat unless he's a real dummy."