McCain is only considered a centrist because the Republican Party as a whole has swung so far to the right. He doesn't fit in because he's not a hard-core free-market ideologue nor is he a fundamentalist. The best line from the article? "Republican voters, meanwhile, are more likely than Democrats to view the Senator in a negative light: 16% of them do, compared to just 4% of Democrats and 8% of Independents."

Having said that, it seems like the best we can hope for at the moment is damage-limitation. Sigh. Go Kerry-Whoever.