I saw this image on Twitter earlier, claiming that they're actual campaign badges for Richard Nixon's 1972 election:
I believe this is a notable claim, as some other websites report on them (though this link at least claims that it was an unofficial slogan):
One of the more humorous, unofficial, historic campaign slogans was "They Can't Lick Our Dick," which was used on at least four different campaign buttons for Richard Nixon.
Is there any evidence that pins sporting the slogan "They Can't Lick our Dick" were in use for the 1972 presidential election, or have they been produced after the fact?