Wingers like Savage are continuing the long conservative tradition of stoking fear and exploiting public distress to turn one group against another. Race, in particular, is an easy fault line to work with and has been crucial to long-term conservative strategy and short-term electoral success.
For example, in early America, the Southern Slaveocracy worked diligently to keep three main groups resentful of one another and in vain competition: poor Whites, Black slaves, and Native Americans. Occasionally there were stories of two or three of these groups uniting to resist the autocrats (poor Whites joining in a slave revolt, runaway slaves joining fugitive Indian tribes, etc.) but such unity was crushed with all possible speed. It wasn't so much the danger of any one particular local uprising that stirred such quick reaction from the Southern Nobles as the creeping fear that such uprisings might be contagious, that they could demonstrate a possibility not previously considered by the great majority of people: reordering society for the benefit of the many rather than the benefit of the few big owners. But as long as the poor White farmers competed with slave labor and poor White frontier families were fighting with Indians, the Established Order was safe.
In the North--really all over the country--you could follow the same story, with different actors. The Irish immigrants must hate the Chinese immigrants and the German immigrants must hate the Italian immigrants, and so on. They must be played against one another, to ensure that they never stand together, organize, and improve their common condition by remaking the whole system. Over the course of our history, the only way for the "profit first" system to prevail against the push for a "people first" system was for the powerful to keep the people divided and distracted.
Today, the same divide-and-conquer impulse is behind the conservatives' anti-Mexican campaign. Think about it, if we weren't distracted by hyped up fears and feuds, it wouldn't be long before we won medical coverage for every American, a full employment program, a reverse of the always-increasing military spending, a "Green New Deal" to name a few things.
But if half of this latest anti-minority effort is part of the long-term strategy on the part of what Americans once called the Money Power, then the other half is the short-term, tactical maneuvering of Republican politicians and conservative media personalities. For over 40 years, the Republican coalition won in large part by exploiting White resentment and fear of Blacks. The "Southern Strategy" worked for a long time. But the country has grown more diverse and more tolerant, so the strategy doesn't work for a national party anymore. The problem for Republicans is that after doing this for so long they can't simply turn the party's message around on a dime. For one, the GOP is largely dominated by people who were won over by the racial and cultural wedge issues and who aren't going to give them up easily. The other reason is that feeding red meat to this crowd is not just a tool of big business, it is big business (talk radio, Fox News, the pop culture surrounding Sarah Palin, etc). There is an eager audience who eats this stuff up.
So Michael Savage and his ilk fill the airwaves with a familiar anti-minority tune, and Republican politicians almost have to dance along. The difference is that, in 2009, most people are sick and tired of it. The Savage gang is playing for a smaller and smaller crowd, as reasonable people drift away and the political balance continues to shift.