It’s the most exciting replacement fight in years. Centrist swing vote Justice Anthony Kennedy is retiring and conservatives expect the president to replace him with a true conservative. Liberals are scared to death he’ll do that.

As the Supreme Court’s swing voter, Kennedy led to a balance between conservative and liberal decisions. Sometimes he voted with the liberals. His was the vote that imposed same-sex marriage on the country in Obergefell. Sometimes he voted with the conservatives. His deciding vote upheld Trump’s travel ban this past week. In District of Columbia v. Heller, he tipped the balance to the conservatives to decide that Washington, D.C. could not ban a police officer from having a gun at home.

The President’s Pledge

In his campaign, Trump pledged to appoint conservative judges and justices. If he keeps that pledge, conservatives will have a 5 to 4 advantage. Anyone he nominates is likely — though definitely not certain — to be approved, because Republicans control the Senate 51-49.

They only need a simple majority to confirm a justice. The party abolished the filibuster rule, which had effectively required 60 votes, during Justice Neil Gorsuch’s confirmation process last year.

Trump says he will choose a replacement justice from a list of 25 potential nominees he issued last year. He updated the list in November to include five more names. Trump has promised to nominate only pro-life justices. On Wednesday, he described his list as “a very excellent list of great, talented, highly educated, highly intelligent, hopefully tremendous people.”

The Weekly Standard‘s Fred Barnes identified five frontrunners. All five currently serve on one of the appeals courts. They are all younger judges. One is a woman. They don’t have extensive records by which we can judge their philosophies, but from what can be gleaned they all appear fairly conservative.

Here are the five.

Amy Barrett

Amy Barrett, 46, serves as an appeals judge on the Seventh Circuit. She previously clerked for Justice Antonin Scalia. She taught at Notre Dame’s law school. During her confirmation hearing under President Trump, Democrats attacked her Catholic faith. Sen. Diane Feinstein famously declared, “The dogma lives loudly within you.” However, Barrett co-authored a paper on Catholic judges that concluded: Catholics judges “cannot — nor should they try to — align our legal system with the Church’s moral teaching whenever the two diverge. They should, however, conform their own behavior to the Church’s standard.”

Barrett signed a letter from the Becket Fund criticizing Obamacare’s requirement that employers provide contraceptive coverage. She authored a paper arguing Roe v. Wade was erroneous.

Thomas Hardiman

Thomas Hardiman, 52, was appointed by George W. Bush to the Third Circuit. Trump had considered him to replace Scalia, but chose Neil Gorsuch instead. Trump’s sister Maryanne Trump, who serves on the Third Circuit with him, supports him enthusiastically.

Trump advisor Leonard Leo says his philosophy is in the mold of Scalia’s. He has spoken at Federalist Society meetings, and has ruled conservatively on criminal justice issues. In Busch v. Marple Newton School District (2008), he defended evangelical parents who wanted to read the Bible during a kindergarten show and tell. In another case he dissented from an opinion which held that a New Jersey law could restrict gun possession without a permit.

Brett Kavanaugh

Brett Kavanagh, 53, serves on the U.S. Court of Appeals for the District of Columbia Circuit. He served in several positions under George W. Bush, including legal counsel. He played a lead role under Kenneth Starr drafting the 1998 Starr Report, which recommended impeaching President Bill Clinton.

In Priests for Life v. HHS, Kavanagh opined that Obamacare’s requirement that Catholic religious organizations provide free contraceptives violated the Religious Freedom Restoration Act. Kavanagh dissented from an opinion that required the government to obtain an abortion for an illegal immigrant teen in U.S. custody. He clerked for Anthony Kennedy. CNN speculates that he is the leading contender.

Raymond Kethledge

Age 51, the Michigan resident was appointed to the Sixth Circuit by George W. Bush. Raymond Kethledge clerked for Justice Kennedy. He described himself as a textualist — like Scalia but unlike Kennedy — when he was confirmed to the circuit court.

He has made several conservative decisions. He criticized the IRS for failing to turn over documents related to discrimination against conservative groups. He also sided with the Ohio GOP to disqualify certain votes. He ruled against the Equal Employment Opportunity Commission, which had sued the test prep company Kaplan, claiming background and credit checks discriminated against minorities.

Amul Thapar

Amul Thapar, 49, serves on the United States Court of Appeals for the Sixth Circuit. He voted in favor of Michigan government opening a meeting with a prayer. Professor Brian Fitzpatrick of Vanderbilt Law School says he is a legal thinker in the mold of Scalia and Justice Clarence Thomas. He identifies himself as a textualist.

Wild Card Names

Other sources suggest a couple of wild card names. Inside sources say Trump is considering Senator Mike Lee (R-Utah), 47. Lee has a solid record as a conservative in Congress. He clerked twice for Justice Samuel Alito. He has never served as a judge. Sen. Ted Cruz calls him “the single best choice President Trump could make.” His brother is also on the list.

Donald Trump, Jr., tweeted that Fox News host Jeanine Pirro would make a good justice. Trump has appeared on her show. Lee appears to be a real possibility, Pirro not.

Trump said he will announce his pick on July 9, and that two candidates he’s considering are women.

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