President Donald Trump will announce his pick for the U.S. Supreme Court tomorrow.

The president originally said he would announce his nominee to replace the late Justice Antonin Scalia on Thursday. This morning, he changed that schedule.

"I have made my decision on who I will nominate for The United States Supreme Court. It will be announced live on Tuesday at 8 p.m." ET (7 p.m. CT), the president said via Twitter Monday morning.

The announcement comes just as controversy swirls over Trump's order that places a moratorium on immigration from seven predominately Muslim countries. The president has indicated he plans to appoint justices that will support his immigration policies, as well as right-to-life legislation.

Any High Court pick faces what could be a bruising Senate confirmation hearing in the first major showdown of the Trump administration. Those hearings are expected to start in March.

Trump picks

During the presidential campaign, Trump produced a list of 20 possible Supreme Court nominees. That list has been whittled down and the president is reportedly choosing between three candidates: appellate judges Neil Gorusch, Thomas Hardiman and William "Bill" Pryor. Pryor, a judge on the Atlanta-based Eleventh Circuit Court of Appeals, is a former Alabama Attorney General.

Trump has met with Senate leaders over the pick in recent weeks.

Who is the leading candidate?

The website Fantasy SCOTUS - which applies the fantasy football model to the High Court pick - has Gorsuch ahead, followed by Pryor. Hardiman doesn't appear until number nine on the list.

Gorsuch has pick up 10 votes in the last 24 hours, more than triple that of any other potential Trump pick.

Gorsuch is considered a strict constitutionalist who would vote along socially conservative lines. The Colorado native is 49 and is a graduate of Columbia University, Harvard University and Oxford University.