President Trump is announcing the selection of his second Supreme Court justice Monday evening at 5 p.m. (Alaska).

Within a few days of Justice Anthony Kennedy's announcement that he would retire from the court this summer, Mr. Trump had narrowed the field to three: Judges Brett Kavanaugh, Amy Coney Barrett, and Raymond Kethledge -- all young and all viewed as conservative.

But by Sunday, CBS News chief White House correspondent Major Garrett reported that two candidates had risen to the top of the list -- Kavanaugh and a new candidate, Judge Thomas Hardiman, who was the runner-up to Neil Gorsuch for the president's first Supreme Court nomination.

The president updated reporters on the status of his decision as he arrived back at the White House Sunday. "Getting very close, very close," he said with a wave.

Leonard Leo on Trump pick

Leonard leo, executive vice president of the Federalist Society, who helped craft the list of potential supreme court candidates for Mr. Trump, told CBS This Morning on Monday that the president wants to get his pick "right" like he did with Neil Gorsuch.

"He spent a pretty significant amount of time over the weekend asking questions, talking to people, thinking about this further," Leo said. "This is a really big decision for him. As you may remember, he spent a good part of his campaign talking about this issue; this was a big reason why people voted for him."

Leo told CBS that Mr. Trump is focusing on a candidate that is "extraordinarily well-qualified" as well as "someone who's going to be courageous, independent and fair."

Who is top contender?

CBS News' Jan Crawford tells CBSN that while there may not be one clear "slam dunk" nominee, Judges Kethledge and Hardiman might be easier to be confirmed more quickly than the other candidates Mr. Trump is considering to fill the vacant seat.

Crawford says that Senate Majority Leader Mitch McConnell, however, had reiterated to the White House that the president is still in the Republican party which controls both the House and Senate and that now is the time to "go bold" with his pick.

As for who might be a front runner, Judge Kavanaugh continues to check off all the boxes for Mr. Trump with his elite qualifications but that his confirmation process could potentially take longer. Crawford says that Kavanaugh is seen as a "real intellectual force as a conservative legal thinker on the court" making him the ideal pick to go head to head with someone like Justice Elena Kagan on the bench.

Hardiman and Barrett, meanwhile, would be the only nominees outside the Ivy League, bringing some diversity on the court.

The nuclear option

When President Trump announces his replacement for retiring Supreme Court Justice Anthony Kennedy on Friday night, his nominee will only need 51 votes in the U.S. Senate to be confirmed.

But for the vast majority of American history, nominees for nation's highest court effectively needed at least 60 votes, which often required some bipartisan support for the president's pick. Otherwise, a filibuster could hold up a nomination indefinitely.

Even though Mr. Trump's new nominee won't have to get 60 votes because of the nuclear option, getting to 51 might still be a struggle. Most -- though not all -- Democrats appear dead set against confirming anyone Mr. Trump nominates, and Republicans only have 51 votes there to begin with.

This means that Republicans will likely have to stay united in supporting Mr. Trump's pick, which could get complicated if moderate GOP Sens. Lisa Murkowski and Susan Collins feel the nominee is too conservative, particularly on abortion rights.

Trump zeroing in on final decision

Mr. Trump still appears to be closing in on his final decision after telling reporters on Sunday that he would have a final decision "sometime by 12:00" on Monday.

"I'm getting very close to making a final decision and I believe this person will do a great job," Mr. Trump told reporters after leaving New Jersey this past weekend. As of Monday afternoon, he's given no indication which way he's leaning, tweeting that "the most important decision a U.S. President can make is the selection of a Supreme Court Justice - Will be announced tonight at 9:00 P.M."

CBS News' Jan Crawford reports that the president has likely made his decision by now but that the final name will likely not leak out, similar to his last pick in Neil Gorsuch.

On the president's schedule ahead of his primetime pick: lunch with the vice president before announcing his final decision for associate justice in the East Room.

Jon Kyl named Supreme Court "sherpa"

White House spokesman Raj Shah said in a statement that former Sen. Jon Kyl "has agreed to serve as the Sherpa for the President's nominee to the Supreme Court." Kyl was Senator for Arizona for 18 years from 1995 to 2013. He served on the Senate Judiciary Committee during the confirmations of 4 of the last 5 justices who have joined the Supreme Court

Sherpas to the nominee will act as a guide during the confirmation process -- helping to set up meetings with lawmakers on Capitol Hill and preparing for the eventual confirmation hearing.

How did we get here? Justice Kennedy resignation

Mr. Trump is filling the vacant seat left by Supreme Court Associate Justice Anthony Kennedy who announced he would retire from the highest court on the final day of Supreme Court decisions for this year's term.

In a letter, he told Mr. Trump that effective July 31, he would end "regular active status as an Associate Justice of the Supreme Court, while continuing to serve in a senior status."

Kennedy called it the "highest of honors to serve on this Court," and he expressed his "profound gratitude for having had the privilege to seek in each case how best to know, interpret, and defend the Constitution and the laws that must always conform to its mandates and promises."

President Trump's potential Supreme Court nominees

Raymond Kethledge

Kethledge, a graduate of the University of Michigan Law School, is a judge on the U.S. Court of Appeals for the Sixth Circuit in Michigan. Like Kavanaugh, 51-year-old Kethledge clerked for Kennedy.

As Mr. Trump often touts the need to protect the Second Amendment, Kethledge is known for his defense of that amendment. In 2016 in Tyler v. Hillsdale County Sheriff's Department, for instance, Kethledge joined a concurring opinion holding that a federal statute permanently prohibiting a person who had been involuntarily committed nearly three decades before from owning a gun was unconstitutional.

Kethledge's job has given him an opportunity to issue opinions on a number of immigration cases, in a time when Mr. Trump's approach to immigration could very well land more cases in the highest court in the land.

Brett Kavanaugh

Kavanaugh is still young at 53, but has extensive experience on the bench. The Yale Law School graduate has served as a judge on the U.S. Court of Appeals for the D.C. Circuit since 2006. Through the years, he has issued scores of opinions, dissents and concurrences. He clerked for Kennedy, the man he would be replacing. And he gained attention from his time working for former independent counsel Ken Starr during the investigation into then-President Bill Clinton. He is the only one of the top three with a law degree from an Ivy League school.

Kavanaugh has a track record of siding with religious organizations over governments and other groups that challenge them, a particularly attractive trait to conservatives. In Priests for Life v. HHS, Kavanaugh declared the Obamacare contraceptive mandate violated constitutional rights to religious liberty.

On the issue of abortion -- key for many conservatives -- Kavanaugh dissented from a recent ruling requiring an undocumented immigrant minor who wanted an abortion to be granted access to one. The D.C. Circuit Court of Appeals overturned the decision by a three-judge panel of the same court that included Kavanaugh.

Amy Coney Barrett

At 46, Barrett is the youngest of the president's top picks -- an advantage for conservatives who want a Trump appointee to serve as long as possible on the land's highest court. If selected and confirmed, Barrett would be the only conservative female justice. The current female justices on the court have been nominated by Democratic presidents and are considered liberal.

Potentially working against Barrett is her relatively short tenure in federal court. The Notre Dame Law School graduate has only served on the U.S. Court of Appeals for the Seventh Circuit since fall 2017. Because she has served on the bench for such a short period of time, she has few opinions to dissect that could offer insight into her judicial philosophy and predict potential future positions.

Before serving on the Seventh Circuit, Barrett, a mother of seven, was a professor at Notre Dame Law School.

Barrett, a Catholic, is considered reliably socially conservative, and conservatives consider her as someone who will faithfully uphold principles of religious liberty from the bench.

Thomas Hardiman

Hardiman has an appealing life story -- the first person in his family to go to college, he attended the University of Notre Dame as an undergraduate and then later financed his law degree at the Georgetown University by driving a taxi. If confirmed, Hardiman would be the only justice on the court who did not attend Harvard or Yale Law School.

He became a federal district judge at 37 years of age and was appointed to the 3rd Circuit in 2007. And Hardiman just celebrated his 53rd birthday on July 8.

Hardiman has sided with jails seeking to strip-search inmates arrested for even minor offenses, and he has also supported gun rights. He dissented in a 2013 case that upheld a New Jersey law to strengthen requirements for carrying a handgun in public.

Justice Kennedy's key swing votes

For three decades on a divided Supreme Court, Associate Justice Anthony Kennedy was often the swing vote who determined the fate of monumental cases.

Here are some of the key cases he decided:

Gay marriage: Obergefell v. Hodges, 2015

Kennedy was in the 5-4 majority that decided in June 2015 the Constitution that guarantees the right to same-sex marriage. The decision invalidated all existing bans on same-sex marriage across the country and solidified the rights of individuals in all 50 states to wed. It was Kennedy who authored the majority opinion.

Abortion: Planned Parenthood v. Casey, 1992

In Planned Parenthood v. Casey, the court was poised to overturn the essence of Roe v. Wade -- but Kennedy sided with the plurality who deemed the state is generally banned from prohibiting most abortions. He decided to affirm the "essential holding," aka the basic principle, of Roe v. Wade.

Corporate spending in elections: Citizens United v. FEC, 2010

Kennedy sided with the court's conservatives to rule that the government cannot limit corporate spending in elections under the First Amendment. The ruling, which both conservative and liberal groups have taken advantage of in election cycles since, has certainly made a lasting impact in politics. Kennedy wrote the majority opinion in that 5-4 decision.

Affirmative action: Fisher v. University of Texas, 2016

For the first time in his career, Kennedy sided in favor of affirmative action in a 2016 case in which the Court rejected a challenge to a race-conscious admissions program at the University of Texas at Austin. The 4-3 decision, in which Kennedy sided with the majority, determined that such a program is legal under the equal protection clause of the 14th Amendment. The country's highest court upheld the decision of Fifth Circuit court.

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