Even as Republicans press ahead with plans to begin hearings on Judge Amy Coney Barrett’s nomination to the U.AS. Supreme Court, there are still potential hazards in the way of a confirmation vote.

As SCOTUSblog’s Katie Barlow writes, the Senate Judiciary Committee is not constitutionally required to hold hearings, or even vote on a nomination. It is possible Sen. Mitch McConnell could bypass the Committee entirely, and bring Barrett’s nomination to the full Senate.

Barlow writes this “would be provocative,” because the Judiciary Committee has held hearings for nearly a century.

The real, constitutional issues come when the full Senate votes:

Article I requires a quorum to be present for the Senate to conduct business. In 1892, the Supreme Court held that each house of Congress determines for itself when a quorum is present. Under the current rules, a quorum consists of 51 senators physically present on the Senate floor. (Vice President Mike Pence, though the president of the Senate, does not count for the purposes of creating a quorum.) McConnell, therefore, needs 51 members present to hold a vote on Barrett’s nomination. Right now, with Lee, Tillis and Johnson in isolation, he does not have 51 healthy Republican senators, and so Democrats can use procedural tools to deny a quorum and block the full Senate from conducting business.

The Senate could change its own rules to implement proxy voting, which would allow Republicans to create a quorum and hold votes without all of their members being physically present — but it would need a quorum present to vote for such a rule change. McConnell would also need two-thirds of the body to invoke cloture on a rule change — unless he deployed the so-called “nuclear option.”

While these are all hypotheticals (and Barlow provides more at the link), the possibility Sen. McConnell may have to use all of his formidable skills to bring Barrett’s nomination to a successful conclusion cannot be dismissed.

Even if the Barrett nomination is delayed, a vote could still occur in the post-Election Day, lame-duck session.