Take Senate Democrats, who are eager to justify the demand that Judge Gorsuch attract at minimum the 60 votes needed to overcome a filibuster. The two top Democrats, Senators Chuck Schumer of New York and Richard J. Durbin of Illinois, have said Judge Gorsuch should have to meet the same “standard” of surpassing 60 votes that Justices Sonia Sotomayor and Elena Kagan did when President Barack Obama nominated them to the Supreme Court. While it’s true that both received more than 60 votes, neither was required to overcome such a “bar” — it was just where they ended up.

In fact, Republicans talked Harry Reid, then the majority leader, out of taking the official procedural steps to require 60 votes for the confirmation of Justice Kagan in 2010, saying they did not want to be accused later of mounting a filibuster against her. Mr. Schumer recently had to correct his assertion that Republicans had insisted on 60 votes for Mr. Obama’s two picks.

Then there is Mr. McConnell’s frequent call for Democrats to simply give Mr. Trump the same consideration that Republicans gave Presidents Obama and Bill Clinton with their Supreme Court nominees. That particular statement really grates on Democrats and their allies given that Mr. McConnell led Senate Republicans last year in denying Judge Merrick B. Garland so much as a hearing on his nomination.

But Mr. McConnell says he is referring to Mr. Obama’s two “first-term” picks, and not the Garland nomination of the second term, even though there is no prohibition on making a nomination late in a term.

Democrats offer their own ammunition when it comes to opposing Supreme Court picks who previously sailed through the Senate. Mr. Schumer’s office has pointed out that Mr. McConnell and Senator Charles E. Grassley, the Iowa Republican who leads the Judiciary Committee, did not object to the confirmation of Justice Sotomayor to a District Court seat in New York in August 1992 even though they opposed her 2009 nomination to the Supreme Court.

What Mr. Schumer’s office does not say is that both of those Republican senators voted against her confirmation to an appeals court in October 1998 when it was approved 68 to 28, an elevation that put her in line for her eventual Supreme Court seat.