No it isn’t.
Or for a longer answer: No it isn’t, but it’s probably useful to explain just what political parties are doing on election.
Every time an election comes around, there’s normally a round of complaints about how terrible it is that so-and-so was out campaigning on election day, and they shouldn’t be allowed and besides, isn’t it illegal to campaign then anyway? Social media has amplified this to the point where I’ve heard of people from all parties organising polling day trips to help out on election day being told they’ll be reported to the police for it.
There are some regulations that affect polling day activities, but those are on the broadcast media who can’t report campaign events or polling, and are pretty much limited to reporting that election day is happening and that people — usually represented by shots of the party leaders turning up at their local polling stations — are voting. That’s also one of the big reasons why parties aren’t staging big national events on election day because they won’t get any coverage on TV for them, and there’s no point getting stuff in the next day’s newspapers.
But, while there might not be much about it on TV, election campaigning is going on right up until polling stations close at 10pm. The difference is that after weeks and months before of persuading people to vote for you and attempting to identify who will vote for you, polling day is focused almost entirely on getting the vote out.
Think of it like this: each party has a long list of the people they think are going to vote for them and they want to get as many of those people out to vote as possible. You can’t win an election on polling day, but you can definitely lose one if you don’t do enough work to get out your voters while your opponents are. Consider this example: Party A has 10,000 people it expects to vote for it, while Party B only has 8000. If voters turn out at equal rates, Party A will win, but if they can only get 60% (6000) of their voters out, while party B work harder and get 80% (6400) of theirs out, Party B win.
So on election day, they’re doing all they can to make sure their voters turn out, delivering leaflets, calling them, and knocking on their doors to remind them, and also arranging lifts…