Canada

makes sense, i was a little worried when i saw a pencil in the booth but this makes me feel better.

The UK election commission recommends pencils as there was a worry that ink could become invisible in the ballot box if there was an organised effort to replace the pens. But that's the provided writing implement. I don't think there is any rule for bringing your own. And I don't think the counters have time to invalidate a vote because of marking type.

Interesting how it's changed over the years. I was a deputy returning officer a few elections ago and the official line then was that pencil was the accepted implement because it was less likely to smudge and spoil a ballot.

Of course, you'd have to make sure the pens were all the same colour, otherwise it could be used to mark ballots (I. E. I use my green pen to prove I voted for so and so). That could circumvent the secret ballot.

In the small town I now call home, there were complainers on the local facebook page saying their pencil marks could be erased. What utter idiots, it gets folded up and put in a box by your own hand so when would someone be erasing it. The volunteer workers said no one steals the pencils but people take pens so even if you put equal amounts on the table the pens will soon be gone.

The righty's are worried that high turnout means a loss for them since voter apathy is their only surefire way of winning.