( I open the door)
Salesman : Don't worry, I'm not a salesman (lie) and I am not one of those awful politicians who knock on doors to annoy people.
Me : Errm, I am one of the politicians who knock on doors. I don't do it to annoy people. Possibly not the greatest start.
Salesman : No. I don't suppose you are interested in switching electrical suppliers ?
Me : No.