I do the same thing..keep my W '04 sticker in the rear window on the INSIDE so I can remove it when I park. I had my car keyed in the 2000 election and it cost a fortune to have the car repainted, so I am more careful now. I live in the area of the People's Republic of Portland, OR.
We spent a few days the summer of 2000 in Portland with my Bush/Cheney stickers, second amendment stickers and anti Watermelon stickers on my Bronco.
A younger relative, whom, we visited was afraid that I or my wife would get killed or put him in danger. To placate him, at night I parked my Bronco in his garage and he parked his unstickered vehicle in the driveway. He lived in NE Portland at that time.