In my very first year as a trainee in an agency I had the chance to join a team which was working for SPD party. It was the year when there was Bundestagswahl to elect the next Bundeskanzler in Germany. All major parties identified the political centre to be the spot where the decision falls.
It happens to be the SPD as the socialist party in the race to claim the red color for themselves and it also happens that the red color is placed right in the middle of the German flag.
So to me the idea was too simple to not make it: "The centre in Germany is red."
Btw: The SPD won the election back then.