A true conservative shouldn't be racist because I believe a true conservative should let free markets reign with some restrictions. But there is no reason why restrictions should be based on race. Look at the belief system of Alan Keyes. He is an African American conservative. I bet the mainstream media would like to make people think that there is no such thing.
I don't know if these racist accusations are true or not. It did strike me that since liberals cannot defeat conservatives in the arena of debate, they have to dig up some dirt and slander conservatives personally.