Numbers

If you were looking for past performance of German elections and the effect on the CDU, then here are some examples:

2013:
- CDU and Merkel: 16.2 million votes
- CSU (out of Bavaria): 3.5 million votes

2009:
- CDU and Merkel: 13.8 million votes
- CSU: 3.2 million votes

2005: (the year she lost)
- CDU and Merkel: 15.4 million votes
- CSU: 3.9 million votes

In a typical German election (using the last four), between 43 and 48 million Germans will vote....with a 65 to 70 percent turn-out of registered voters.  The CSU rarely gets above the 3.9 million vote mark (2002 was the exception, with their guy as the Chancellor candidate between the CDU and CSU.....with 4.3 million Bavarian voters).

The odds in 2017's election?  You can be fairly sure that she won't exceed the 2009 number (13.8 million votes), and it's possible that she won't cross the 12 million point, with some normal CDU voters going toward the AfD.

The obvious question left.....will disenchanted voters from the SPD also fall into this issue, and lessen their average (typically 12 to 16 million)?  They've had one great year in the past four elections with 20 million.