It depends on which parties you're talking about. Many individuals on the more conservative side of German politics (DNVP, DVP, BVP) ended up cooperating with/working under Hitler after the dissolution of their respective parties in 1933. As all parties other than the NSDAP were banned after this time, these politicians had to switch their allegience if they wished to keep their political careers alive. A good example of this is seen in the figure of Hjalmar Schacht, a relatively liberal figure who worked as the economics minister under the Nazi regime until 1937 (although he had shifted his support to the NSDAP before 1933).

Of course, the first concentration camps were used to imprison the political opponants of Nazism (communists, socialists, social democrats). The first such camp was Dachau, which would serve as a prototype for the other installations in the camp system. However, while we often treat 'concentration camp' and 'death camp' synonymously when discussing the Nazi regime, this is inaccurate, particularly as early as 1933. While many political opponants were executed by Nazi organs in these early years, many also ultimately survived their initial incarceration, and were forced into silence and retirement.