To provide a smidge more detail, the movie Groundhog Day is about a man reliving the same day over and over and over. Every time he wakes up it's Groundhog Day again, and people always say the same things and do the same things over and over, and he's the only one who is aware of the infinite repetition and who is capable of doing things differently.
In the present day, the phrase could be used in a joking way to express disapproval of a newcomer who sets some precedent for change in the social environment.
I would caution, however, that it originated as an expression of resignation and disapproval of racial minorities moving into previously all-white neighborhoods. Key drivers of housing integration in the U.S. include Shelley v. Kraemer, a 1948 case in which the U.S. Supreme Court ruled that racial covenants were unconstitutional; the 1968 Fair Housing Act, which banned discrimination in housing; and court-mandated school desegregation busing which began in the 1970s.
Many in the white majority considered integration undesirable, either because they believed the newcomers would make bad neighbors, or because they believed that white disinclination to live in integrated neighborhoods would mean a decline in property values, and or both. If one minority household moved in, others would soon follow, and the neighborhood, it was said, would go into terminal decline.
This sense of the phrase is far from forgotten. Even if you intend to refer to some other characteristic of a newcomer, it may be interpreted as singling out his or her race, a phenomenon which is the basis for the entire South Park episode “Here Comes the Neighborhood.”
Best Answer
It goes back to at least 1542, so I can confidently say there are no racist origins in the expression.
Apparently it first appeared in English in Nicolas Udall's collection of Erasmus's aphorisms - translated in 1542, but ultimately deriving from Plutarch's Moralia in the first century AD.
It's really just an observation that forthright honest people use straightforward words. I doubt the fact that "a spade" happens to be the common example has any special significance, though that obviously wouldn't have worked for Shakespeare in the related rose by any other name.