Washington (CNN) Republican Sen. Josh Hawley has concerns about the President's nominee to take the seat formerly held by Supreme Court Justice Brett Kavanaugh on the powerful DC Circuit Court of Appeals.

A source familiar with the Missouri freshman's thinking confirms that he is questioning the views of Neomi Rao and is currently undecided on whether he will support her nomination. He has expressed that to Senate Majority Leader Mitch McConnell of Kentucky.

Hawley, who serves on the Senate Judiciary Committee, has concerns about the fact that Rao has never been a litigator, according to the source who says Hawley is also unsure of her stance on Roe v. Wade.

Hawley's main concern, however, is Rao's judicial philosophy and the lack of a record on substantive due process. She's never been a litigator on the subject, so he cannot tell how she would act, but her writings indicate she might be okay with substantive due process, according to the source.

The news comes as the Trump administration's judicial confirmation process -- that almost seamlessly pushed through a record number of appellate court nominees as well as two Supreme Court nominees during Trump's first two years in office -- seems to be fraying.

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