blue shift

(US politics) An observed phenomenon in which an apparent early Republican lead after the polls close on the night of an election is diminished by the counting of mail-in ballots later in the evening or in the days after Election Day.

(physics) Alternative form of blueshift. [(physics: astronomy, relativity) A decrease in the wavelength of a photon or of light, corresponding to a higher frequency and a shift toward the blue end of the electromagnetic spectrum.]