Protecting special counsel Robert Mueller is a good government prerogative. It is also a political opportunity, and Sen. Kamala Harris, D-Calif., as been making the most of it amid increased speculation she will make a run for the presidency.

Acronym, a progressive digital firm, noticed that the Kamala Harris for Senate campaign had run around 1,100 Facebook ads asking her supporters to sign a petition to “protect the Mueller investigation” (920 were still active at last glance).