For-show campaigning. She could not let a powerful CDU member like Koch drop, publicly. But her position in the CDU will be strengthened as a result of him losing (and exiting politics, one hopes).

As a backgrounder to DoDo's statements: the Minister-Presidents of the German states have for a long time held a remarkable amount of power. This is because first, the States have a lot of power themselves, second, the states also form the German upper house (Bundesrat), and the Bundesrat is dominated by the CDU (supermajority) to an extent where it can in practice block nearly all legislation.

Four of the current Minister-Presidents of the CDU are part of a political career pact (Andenpakt). A further Andenpakt member is in Merkel's government, and yet another is now President of the European Parliament. So speaking to Roland Koch is not like talking to the Governor of, say, Illinois. He was one of the most powerful politicians in German politics of the last 6-odd years.

Koch:

Y:

_{*Lunatic*, n.
One whose delusions are out of fashion.}