Well, this is quite tricky to write about. I supposed to find information that you get, when you think of German right-winged (or –extremist) parties like the NPD: the average voters come from the new German states (in the east), come from a deprived area, have very uncaring parents and so forth. But in fact that isn’t so. Despite of the fact that the average German republican voter is not too educated, there are not many demographic facts that you could use as a profile for the “typical” republican voter. The only thing that is striking, is that two thirds of the voters are male.
The party has been under the observance of the German Verfassungsschutz because of their nationalist program, but since 2005 they are not longer considered as being right extremist, so it is no relevant party for neo-Nazis to vote (even though there are certainly many voters of the German republicans that are xenophobic and anti-Semitic).
On the republican’s website a young republican candidate says, that he is member of the German republican party because it stands for democracy, freedom and patriotism.
In Bavaria, the conservative party CSU lost many voters to the republicans. Maybe that is a sign for the republican voters being discontent with the way their big conservative party acts, maybe it acts not extreme and hard enough. The “Bundeszentrale für politische Bildung” says, that German republicans are afraid of social and financial decline and so vote for a party with a more extreme party program. That thought is not too farfetched, I guess, because you can see the same trend in dissatisfied left voters, who change from the big party SPD to the more extreme and more left party “Die Linke” (and it seems to be the same in America, considering the Tea Party - check the blog out for more information).