Bristol Palin's former fiancé Levi Johnston says the thought of Sarah Palin becoming the U.S. president frightens him.

'President Palin' is a phrase that scares me, Johnston, the father of Bristol Palin's son, Tripp, and now author of the book, Deer in the Headlights: My Life in Sarah Palin's Crosshairs, said in an interview with In Touch Weekly.

She's apparently only 5 percent behind Obama [in polls] right now, and that's frightening me, Johnston said. I'm figuring I might have to move to Canada because she's gonna kick me out of the country if she wins!

Johnston, who attained sudden celebrity in August 2008 when the Alaska governor and U.S. vice presidential candidate announced that her daughter was pregnant with his baby, called Bristol's book, Not Afraid of Life: My Journey So Far,  unbelievably disgusting.

For somebody to date someone for several years, have a child, almost get married twice, you don't come out and say your virginity was stolen. Let's be real, lady! he said in the interview.

Johnston added that Joe McGinniss' book, The Rogue: Searching for the Real Sarah Palin, was different from Bristol's work, while asserting that his own work was full of 100 percent truth.

I lived there. I've known them for a long, long time now and I was there, and everything in there's a fact, he said.

Johnston, who posed almost nude in Playgirl, also talked about the crazy offers he has received, including half a million dollars to act in pornographic films. Half a million dollars to masturbate on camera and do a porno with the Sarah Palin look-alike who did 'Nailin' Palin.' We didn't think about it; it was a hangup phone call. I've got so much horrible stuff, Johnston said.