They can manipulate in many ways. In Trempealeau County about 10 years ago one conservative board member spilled coffee on a few of his nomination papers, and rewrote them, and was disqualified for doing so. The democrat County Clerk pushed to have him forced out. The State elections board finally agreed, even though they stated that the intent of the signer should be respected. Yes, the elections officials also manipulate. This was only a small percentage of signatures.
There is a lot of internal manipulation in La Crosse county government.