[stnikolauswagne]

I dont think anyone would ever say „Ich bin christemokrat“, a much more common saying (at least in the area where I live or the area I grew up) would be „Ich bin CDU-Wähler“/I am a CDU-Voter. This is coincidentally how my parents would describe their political leanings (SPD).

[Firadeoclus]

Certainly some people do say "Ich bin Christdemokrat", but that would usually be active party members, not just voters.