If Republicans blow up the Supreme Court filibuster, is the legislative filibuster next?

Without the current filibuster rule on legislation, Democrats, should they dominate Washington again one day, could seek a large increase in the minimum wage, increased Social Security benefits, paid family leave or Medicare for all. And they would need only a simple majority to do it.

Similarly, Republicans could pass large permanent tax cuts, oil drilling in the Arctic or a national concealed-carry gun law. Such power is something that President Trump might see as quite delicious, and something that he may well push for if Republicans confirm Judge Neil M. Gorsuch for the Supreme Court without meaningful support from Democrats.

“There is not a single senator from the majority who thinks we ought to change the legislative filibuster,” said Senator Mitch McConnell, Republican of Kentucky and the majority leader. He is expected to move this week to remove the 60-vote threshold to proceed with a vote on Judge Gorsuch’s nomination. But, that, he insisted, would be the end of it.

But many Democrats said they were skeptical of the claim. “I have seen the process deteriorate,” said Senator Benjamin L. Cardin, Democrat of Maryland. “So do I believe Mitch McConnell would change the rules again? Yes.”