Every time I've been passed too closely, it's because I've left the driver enough room to do so.
I would have to say that the majority of the time, this has been true for me.
I did have the exception happen last week.
Two lane road, no shoulder, it's early morning before sunrise. I was in the middle/left tire track of the lane. A vehicle is coming from both directions and the idiot coming from behind pulled into the opposite lane to pass anyway. I'm ducking for the non-existent shoulder/ditch expecting collision. The oncoming truck, came to a complete stop in order to allow the passer to get past - it was still a near miss - just a couple of feet. I could hear the driver of the stopped vehicle swearing as went on by.. not at me but the driver of the SUV who passed me.