I'm not from AZ, but as an outsider I'd say McCain's need to collect all those endorsements reflects a degree of panic on his part. Why in the world does a four term Senator need to do that?
Congress' approval has never been lower. There is a big anti-incumbent mood. McCain may have lots of endorsements and may be up in the polls right now, but, hey, so was Coakley until the last couple of weeks. I say he's right to be scared.
Hayworth represented his district well until it was redistricted. He voted for spending for american indians spending cuz he felt it was the only way he would get reelected, but he lost.