Historically, Republicans tend to perform poorly when more people vote. So, it's is only natural for some people to think, "it looks like this one is in the bag, there is no need for me to vote. I'll sit this one out."

I apologize for being mean. I'm just sick of people suggesting that voting doesn't matter or can't make a difference. Ours is not a perfect system but it is the best we have at the moment and if voting didn't matter the Coservative assholes wouldn't be trying to make Democracy as difficult as possible.