This quote clearly demonstrates where the hate language comes from:

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One of the comments posted by a video of hate-spewing attendees at a Palin rally was:

"I live in rural Minnesota. I have watched the rise of this kind of ignorance and intolerance march in lock step with the rise and proliferation of conservative talk show hosts. Starting with Limbaugh; we now have hundreds of demagogues trying to scare good honest Americans into voting against their interests and the future of the United States. They've rewritten science, inverted economics and hijacked religion in order to feed their greed and bigotry while corrupting the minds of my neighbors."

So it's RW hate radio, i.e. Rush Limbaugh and his imitators all over the country, along with those on Fox News and other TV channels who parrot the same talking points. What they have done is systematically taken the economy off the table as an election issue, and replaced it Lee Atwater-style personal attacks as the issues. The hate-spewers at the rally are just the echo chamber. I'm sure everyone on DU already knows all this and how it works, but that quote made it crystal-clear.