I don't see it as against my principles if I had to vote for, oh, Romney....Or Paul. There is not anyone here who is in lockstep with every candidate, so it would be reasonable to surmise you compromise your principles every time you vote. So I don't buy the argument, but I do see it as frustration with a party that seems to lose its rudder at times.
I feel I compromise my principles, my beliefs, my family, if I don't do everythig within my power to kick a socialist out of the White House....and his friends. I compare it favorably as a young, newly married guy who needed to support his family....So I held my nose and took some jobs most would feel is beneath them, but I had a family to think of and support, it wasn't just about me anymore.