Why? Because they lie and/or refuse to answer questions.
Example one: McCain’s senior advisor Steve Schmidt was quoted in today Wall Street Journal about whether Sarah Palin had been fully vetted:
This vetting controversy is a faux media scandal designed to destroy the first female Republican nominee for vice president of the United States.
That is nonsense, a blatant lie. Wondering how a presidential candidate made a giant decision (his choice of a VP) is a totally legitimate line of questioning. Even if you support McCain and Palin, you might wonder “did he really know everything? Did he rush into that pick?” To claim that it’s a “faux media scandal” is ridiculous. That is what journalists are supposed to do: ask tough questions.
Example two: this clip from CNN, which has gotten a fair amount of buzz. In it, CNN’s Campbell Brown asks McCain spokesman Tucker Bounds some simple and legitimate questions about Sarah Palin. He ducks and weaves, refusing to answer the questions, and then attacks the journalist for “belittling” Palin. Avoiding questions and sliming people makes the average voter completely tune out these spinmeisters.