Please don't write in any name unless you know the person has been running a "write in" campaign. I have been an election judge in the past, and the number of ballots with write in names (especially joke names such as Santa) was infuriating. It made a long day much longer since we have to manually tabulate every write in vote.

It's better just to leave it blank if you don't want to vote for anyone that is on the ballot.