In chess, a gambit is an opening maneuver intended to draw one's opponent into a position where he can be taken advantage of.  Sometimes a gambit involves the sacrifice of a piece, often a pawn, to entice the opponent.

On Thursday, Senate minority leader Chuck Schumer (D-N.Y.) announced that his caucus would filibuster the confirmation of President Trump's nominee for the Supreme Court, Judge Neil Gorsuch.  Under current Senate rules, Republicans would be unable to stop the filibuster unless eight Democrats cross party lines and provide 60 votes for cloture.

Schumer appears confident that that will not happen.

If the Republicans cannot stop the filibuster, it is likely that they will exercise the so-called "nuclear option" and change the Senate rules to allow the confirmation of Supreme Court nominees on a simple majority vote.  (Republicans will probably do this because Schumer's predecessor, the now retired Harry Reid, changed the rules to allow simple majority votes on Circuit Court and District Court nominees when Democrats previously controlled the Senate.)

And if the Republican change the rules, they'll be playing right into Schumer's hands.

A Gorsuch confirmation would merely restore the ideological balance of the Court to what it was before the death of Justice Scalia in February 2016 – a 4-4 split between liberal s and conservatives with Justice Anthony Kennedy providing the "swing" vote in a number of 5-4 decisions.  Schumer can live with that – after all, Kennedy sided with liberals in blockbuster cases like Lawrence v. Texas and Obergefell v. Hodges, declaring that anal intercourse and gay marriage are "constitutional rights."

While Gorsuch's confirmation wouldn't change much from a legal standpoint, if he is confirmed after a Republican rule change, Schumer can paint Gorsuch as a usurper.  Schumer's gambit is to force the hand of the Republicans to take the political heat for changing the Senate rules, accept the confirmation of Gorsuch as a sacrificial pawn, and then bet that Trump will either a) be impeached before the end of his term or b) lose his re-election bid in 2020, enabling a future Democratic president and a future Democratic Senate to ram three left-wing ideologues onto the court in rapid succession with simple majority votes.

Schumer is planning several moves ahead, for the death or resignation of Kennedy, age 80, and for the death or resignation of Bill Clinton's two reliably left-wing appointees, Ruth Ginsburg (age 84) and Stephen Breyer (age 78).  The replacement of these three aging justices will have a significant impact on the ideological makeup of the Court in the near future.

Schumer knows that history shows that Republicans (e.g., John McCain and Lindsey Graham) are more willing to cross party lines and vote for Democratic nominees than Democrats are to support Republican nominees.  And he also knows that Republican presidents have had a history of getting burned appointing justices they think will be strict constructionist conservatives, only to have those nominees  turn into flaming liberals on the bench (Earl Warren, Harry Blackmun, John Paul Stevens, and David Souter are prime examples).  So a rules change allowing simple majority votes on Supreme Court nominees would favor Democrats for the foreseeable future.

Schumer is an extremely slick, Machiavellian operator.  He's not stupid.  Republicans are going to need to learn how to play hardball with him.

The preferred strategy for Republicans is to break Schumer's power by putting extreme pressure on members of the Democrat minority to defect and confirm Gorsuch without changing the Senate rules.  They should change the rules if Trump has an opportunity to replace Kennedy, Ginsburg, or Breyer in the near future, when the stakes will be significantly higher.