President-elect Donald Trump speaks at the DeltaPlex Arena, December 9, 2016 in Grand Rapids, Michigan. Drew Angerer/Getty Images The crowd at President-elect Donald Trump's victory rally on Friday night started up a familiar chant: "Lock her up." The slogan was a staple of his raucous election campaign, targeting his Democratic opponent, Hillary Clinton.

When the audience revived the chant in Grand Rapids, Michigan, Friday night — more than one month after Trump won the election — the president-elect said, "That plays great before the election — now we don't care, right?"

Trump during his campaign repeatedly vowed to seek criminal prosecution against Clinton for her use of a private email server during her time as secretary of state.

During one fiery exchange at the second presidential debate in October, Trump said if he were elected, he would appoint a special prosecutor to look into Clinton, telling her "You'd be in jail," if he was in the White House.

The next day, when a crowd at one of his rallies began chanting "lock her up," Trump declared "Special prosecutor, here we come."

Two weeks after the election, Trump reversed his position, saying investigating Clinton was "just not something that I feel very strongly about" and "I don't want to hurt the Clintons, I really don't."

Watch Trump say "Now we don't care":