President Trump told reporters the “search for a new justice will begin immediately” after the Wednesday announcement from Justice Anthony Kennedy that he plans to step down from the high court.

The announcement kick-started rampant speculation about whom Trump will pick for what could be the most consequential appointment of his presidency, giving him the opportunity to move the Supreme Court more solidly to the right.

Sources indicated to Fox News six federal appeals court judges -- Thomas Hardiman, Brett Kavanaugh, Amy Coney Barrett, Amul Thapar, Joan Larsen and Raymond Kethledge -- are considered early frontrunners, though others could be under consideration too, as Trump said Wednesday he will choose someone from his previously released list of 25 candidates. All six of these judges are on Trump's list.

Trump himself nominated Thapar, Barrett, and Larsen to their current positions. Hardiman and Thapar were finalists for the seat that went to now-Justice Neil Gorsuch, and were personally interviewed by the president.

KENNEDY ANNOUCNES RETIREMENT, GIVING TRUMP 2ND SUPREME COURT PICK

The White House, in November, released a list of 25 people the president would choose from to fill a Supreme Court vacancy.

According to Leonard Leo of Federalist Society, who has advised the president on judicial picks, it’s possible a vote in the Senate on a Supreme Court nominee could come as early as the last week of September.

The Early Frontrunners:

Thomas Hardiman

Hardiman is on the 3rd Circuit U.S. Court of Appeals, with chambers in Pittsburgh. Hardiman was a finalist for the seat that went to Gorsuch. The Supreme Court affirmed his 2010 ruling that a jail policy of strip-searching all those arrested does not violate the Fourth Amendment's ban on "unreasonable searches and seizures."

Brett Kavanaugh

Kavanaugh is a judge of the United States Court of Appeals for the District of Columbia Circuit. Prior to his appointment in 2006, Kavanaugh served as assistant to the president and staff secretary and was a lawyer in the White House Counsel's Office and in the Solicitor General's Office during the Bush administration. Kavanaugh also served as a law clerk to Kennedy of the Supreme Court.

Amy Coney Barrett

Barrett is a Judge of the United States Court of Appeals for the Seventh Circuit. Prior to her appointment in 2017, Barrett was the Diane and M.O. Miller, II Research Chair in Law and Professor of Law at Notre Dame Law School. Barrett also served as a law clerk to former Justice Antonin Scalia on the Supreme Court.

Amul Thapar

Thapar, who serves on the U.S. Court of Appeals for the Sixth Circuit, was personally interviewed by the president for the seat that went to Gorsuch. Previously, Thapar served on the U.S. District Court for the Eastern District of Kentucky.

Joan Larsen

Larsen, who serves as a Circuit Judge of the United States Court of Appeals for the Sixth Circuit, is a former justice of the Michigan Supreme Court. She is also a former law clerk to Scalia and delivered one of the tributes to the late justice at his memorial service.

Raymond Kethledge

Kethledge, a circuit judge of the United States Court of Appeals for the Sixth Circuit, clerked for Kennedy on the U.S. Supreme Court.

Fox News’ John Roberts contributed to this report.