As I said, it's a difficult act of balancing. As long as they don't use swastikas and keep their rhetoric free of direct Nazi propaganda there is nothing the law can do against them. That's the downside of freedom of speech. They still do have the same view of the world as the original Nazis but have to hide it behind nicer words and other symbols as the original Nazis. They always try to get as close to the border of what's legal and sound as much as the "originals" as possible without violating laws. Sometimes however they do cross the line and that's when they can be prosecuted. For example for inciting hatred against minorities, glorifying / denying the holocaust (they should really finally make up their minds about that...
), direct praise for nazi leaders etc.