There are, apparently, so many ways to falsify votes that it beggars belief.
Votes can be swapped out during the transportation stage. With this method, ballots are loaded in a van, and another batch are unloaded at the central counting center. Ballot stuffing is ubiquitous and can occur at literally any stage of the process. Then, the commission can simply close the doors and simply print new ballots that they then fill out for the candidate of their choice. Nowadays, with mail-in voting, the opportunities for fraud have only multiplied. Back in my state, someone apparently registered me to vote. I got a letter in the mail saying as much. I’d never register to vote and I’d never actually vote. That little chit or check mark can be traced back to you and your family and, eventually, someone might come to your house in the dead of the night because you voted the wrong way one time too many. Paranoia or foresight? Time will tell.
But actual physical vote-swapping is a very crude and blunt method.
It is far easier to harvest ballots en masse from retirees or sick people. Registering the dead to vote is also a tried and true tactic. In the Slavlands, union bosses and entire factories vote as a bloc for one party or another after cutting a deal with the party apparatchiks. No doubt such thing could never occur anywhere but the corrupt Slavlands though. Media ad campaigns are also a staple of any serious political campaign. The fact that people with money and political power strongly believe that the peasants can be convinced to vote one way or the other by a 30 second propaganda fluff piece is probably the most damning indictment against the sanctity of the electoral process in and of itself. There tends to be a correlation between well-funded campaigns and success rates. This means that money buys votes one way or another in a Liberal Democracy. And the oligarchs provide the money for these campaigns, naturally.
Such is life in the freest, fairest and gayest empire in world history.