Some things I have tested:
[X] Turn private browsing on Google Chrome
[X] Use a Proxy Browser (tor browser)
[X] Use a proxy website to redirect to the voting site
[X] Change Lan Settings to use a proxy to access the internet
[X] Change Firefox settings to use a proxy to access the internet
[X] Block port 80 through router settings
All of these still lead to the "Sorry but you have port 80 open, this is to stop voting by proxy address." error..