It's a target-rich environment.
Teachers, union organizers, college professors, columnists, bloggers, journalists, precinct captains, community organizers are all "soft targets. Most federal and state legislators and judges. Also, loudmouth Hollywood types typically only have a small security detail to keep stalkers and paparazzi at bay.
It also occurs to me that the employees of Big Tech (Mozilla, Yahoo, Google, YouTube, etc) represent an easy and readily available source of fluids. They don't allow conservatives to work for them, so no screening is required.