Somewhat of a handwriting expert as I spend half of the time writing back and forth with people due to my deafness and this is how I communicate with people if I don't have my phone on me.

But yes, the penmanship is very similar on each and every ballot.

An obvious similarity here is when you look at the letter "T" in "Texas", the top part is downward sloped and it's pretty much the same on every ballot.