TONIGHT, 9:00pm ET: Watch President Trump announce his Supreme Court nomination on Fox News Channel.

Fox News senior judicial analyst Judge Andrew Napolitano says President Donald Trump has narrowed his Supreme Court nominee list to two names.

The Trump administration has reportedly been preparing information materials on four potential nominees -- appeals court judges Brett Kavanaugh, Raymond Kethledge, Amy Coney Barrett and Thomas Hardiman -- to replace retiring Supreme Court Justice Anthony Kennedy.

On "America's Newsroom," Napolitano said he believes Trump has narrowed the list down to Hardiman and Kethledge, with the announcement set for tonight at 9pm ET. Napolitano said his information is based on conversations with those close to the decision-making process.

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Hardiman, a judge on the U.S. 3th Circuit Court of Appeals, was the runner-up when Trump nominated Neil Gorsuch to replace the late Justice Antonin Scalia last year.

Kethledge, a judge on the 6th Circuit Court of Appeals, has been described as a strict constitutionalist in the mold of Gorsuch.

Napolitano said Trump is focusing on Hardiman and Kethledge because he's concerned about the candidates' "confirmability."

"Sen. Mitch McConnell, the Republican leader in the Senate, said to him, 'We will have issues with Judge Barrett and Judge Kavanaugh that we won't have with Judge Kethledge and Judge Hardiman,'" Napolitano said.

He explained that some Republican lawmakers have expressed apprehension that Barrett and Kavanaugh could be lightning rods on the issue of abortion.

"The fight on abortion will be severe if it's Judge Barrett or Judge Kavanaugh, and the thinking ... is that the president is not in favor of that kind of fight."

Get more insight from Napolitano above, and watch Trump announce his Supreme Court nomination tonight at 9:00pm ET on Fox News Channel.

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