Possibly
Seemd to have happened in Britain during 80's.
Polls between Labour and Tory were fairly tight, but Thatcher won in a landslide.
Many opined at the time that people were ashamed/afraid to say they were going to vote for That bloody Woman.
(or it could have been turnout, who knows)
This election though, I'm not sure which side people would be embarrassed to admit who they were really voting for.
;-)