There are leftwing communists at polling stations who will cheat...BY ANY MEANS NECESSARY.
In my experience, most of the cheating is done by non-ideological patronage employees and contractors. They have to maximize the vote in precincts for which they are responsible and in demographic groups they are held responsible. If they don’t, their sponsor gives the jobs and money to those who do produce the votes.
Of course, this corruption tax only works with big government. So the result is ideological. But the motivation is most often personal.