blue shift
noun/ˈbluː.ʃɪft/
Etymology From blue + shift, referring to the Democratic Party's political color, in the case of the first sense.
1
Government, Politics US 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.
2
Natural sciences, Physical sciences, Physics Alternative Alternative form of blueshift.