Genetics comes to mind as an idea that came from left field. The theory was, however, published in a legitimate journal.
One could make some rules of thumb about how quickly a revolutionary idea will be adopted, and it has nothing to do with the status of the scientist or his politics. New ideas will be quickly accepted if they are correctly phrased in the language of physical science and mathematics; if they address a problem that others are struggling with; and if they are supported by evidence.
Consider the ideas of John Nash, a certified loon. To the extent that his writings were lucid, he had no problem getting them accepted.