One unusual feature of this election campaign is that the minor parties are being squeezed out.
The Liberal Democrats have been crushed by their Coalition record, and UKIP has crumbled after a successful referendum. We've not seen this level of two party politics since 1979.
So, for simplicity's sake, allow me to slim down the election choice to red versus blue.
How do we pick our side?
For many of us, the choice is about values.
For one reason or another, we have an affinity with the policies of the left or the policies of the right.
Perhaps we believe in social equality, equal opportunities, sharing resources and supporting others. Or perhaps we believe in individual rights, civil liberties, low taxation and market forces. We have a strong sense that one of these points of view is fair and correct, and the other is unfair and misguided. Something within us makes us feel the way we do, perhaps our upbringing or our life experience, and underpins our political viewpoint at a fundamental level.
In a two-party system we're the non-floating voters. We cast our vote on policies first, and personalities second. It's sometimes said that we'd vote for a farmyard animal if it were wearing the right coloured rosette, and that's probably true, because we cast our votes based on what parties will do, not on who people are.
For other people, the choice is about personalities.
For these voters, one leading politician appeals, and the other doesn't. One leader says the right things, acts the right way and feels like someone you can trust. The other says things you're uncomfortable with, acts inappropriately and isn't someone you'd like to see in control.
In this election Jeremy Corbyn and Theresa May have sharply contrasting personalities and platforms, perhaps the greatest difference since Margaret Thatcher took on Michael Foot in 1983. A lot of voters are enthused by Jeremy Corbyn and everything he stands for, whereas rather more voters have decided they couldn't possibly vote for Jeremy Corbyn because of who he is. Indeed it could be argued that Jeremy Corbyn himself is the defining feature of this election, sharply dividing voters into those who approve and those who don't, hence the Conservatives' relentless focus on his perceived inadequacies and the strength of Team Theresa.
People who vote based on personality tend to be floating voters, less anchored to a particular viewpoint and more likely to choose their party based on gut feeling. They have no time for the minutiae of manifestos, and pick up the temperature of a campaign through soundbites, acquaintances and the media. They often know just as firmly what they believe, but this can be an emotional response rather than a reasoned position.
As someone who votes according to values, I find it hard to imagine a situation in which I would ever vote based on personality. I may not rate either of the leaders at this particular election, but I am always going to cast my vote for the party which leans the way I do, despite any misgivings at the top. Far better to have a government doing good things ineffectively, I say, than a government doing bad things well.
I see voting by personality as a distraction because I'm confident in my own political beliefs, and perhaps you are too. And yet it's those voting by personality who will decide this election, not those of us who knew who we'd be voting for before it was called.