Here's what they said on the front page: "President Bush had been noncommittal about a constitutional amendment .... But last week Mr. Bush for the first time voiced his support, saying, 'I will support a constitutional amendment which would honor marriage between a man and a woman, codify that.'"
Here's what he really said: "If necessary, I will support a constitutional amendment... [italics mine]" and then said that states have the right to codify their own marriage laws. This is not a straightforward opposition to gay marriage, certainly not a clear support of such an amendment to the Constitution.
I can think of two reasons why they might have done this. (1) They're lazy and don't want to figuring out the details of a more sophisticated position than they're can intelligently handle. This just reveals stupidity, irresponsibility, and lack of effort. (2) They're politically committed to portraying him as less nuanced and complex than he is, since they want him to look evil and lose the election. Since they assume their general readership supports gay marriage, that would be the expected effect. They therefore underestimate the large majority of the country that opposes gay marriage and make him look even more like what many conservatives look like than his position actually warrants. They simultaneously reveal their own agenda in hiding the important details of his view.
So one way they're stupid and irresponsibly lazy but not necessarily evil. The other way they're working hard but irresponsibly devious and conniving, with a touch of stupidity in underestimating how people will see it. Which do you think?