Beginning four days of planned hearings over Judge Gorsuch’s nomination, the proceedings on Monday — light on direct confrontation, heavy on senatorial windiness — set the contours of the debates to come: Democrats raised questions about Judge Gorsuch’s record on issues like workers’ rights and aired concerns about President Trump’s often dim view of the judicial branch. Republicans sought to insulate a plainly well-credentialed jurist whom they hope to install as the court’s next conservative stalwart. And Judge Gorsuch took pains to position himself above politics, on the eve of formal, rigorous questioning from senators on Tuesday.
Leaning often on biography in his speech, Judge Gorsuch cast himself as a humble Westerner, reared on fly-fishing, with malice toward none in his decade as a federal appellate court judge based in Denver.
“My decisions have never reflected a judgment about the people before me, only a judgment about the law and the facts at issue in each particular case,” he said. “A good judge can promise no more than that. And a good judge should guarantee no less.”
A judge who is pleased with every ruling he reaches, Judge Gorsuch added, “is probably a pretty bad judge, stretching for policy results he prefers rather than those the law compels.”
Judge Gorsuch thanked Mr. Trump and did not mention the president’s attacks on the judiciary since taking office, leveled against judges who have ruled against the administration in its push to enact a travel ban from certain predominantly Muslim countries.
He spoke generally of the hard and noble work of judges, perhaps signaling an indirect rebuttal to Mr. Trump’s comments, which he called “disheartening” during private meetings with senators last month.
Judge Gorsuch did not mention Judge Garland on Monday. Democrats, still grappling with how aggressively to oppose this nomination, were eager to fill the void.
“I just want to say I’m deeply disappointed that it’s under these circumstances that we begin our hearings,” Senator Dianne Feinstein of California, the committee’s top Democrat, said at the top of her remarks, citing the “unprecedented treatment” of Judge Garland after the death last year of Justice Antonin G. Scalia.
Senator Michael Bennet, Democrat of Colorado — who introduced Judge Gorsuch, his constituent, alongside the state’s Republican senator, Cory Gardner — said that while it was “tempting” to deny Judge Gorsuch a hearing as well, “two wrongs never make a right.”
Mr. Bennet said he had taken no position on Judge Gorsuch, despite his glowing introduction. Another introductory speaker, Neal K. Katyal, an acting solicitor general under Mr. Obama, endorsed the nominee explicitly, in what Gorsuch allies hope will be a powerful testament to his résumé.
By choosing Judge Gorsuch, Mr. Trump has forced Democrats to reckon with the kind of obstructionism they long lamented from Republicans. In their 10-minute opening statements, Democratic senators made no attempt to quibble with Judge Gorsuch’s qualifications or temperament.
While several members have already said they will vote against him, the prospect of an institution-rattling fight has concerned some more moderate Democrats, particularly those who face re-election in states that Mr. Trump won.
If Judge Gorsuch cannot meet the 60-vote threshold needed to overcome a filibuster, Republicans could change longstanding rules and elevate him on a simple majority vote.
Even some criticisms seemed to hint at the likelihood of Judge Gorsuch being seated, one way or another.
“You’re going to have your hands full with this president,” Senator Richard J. Durbin, Democrat of Illinois, said at one point during a discussion of executive branch overreach, seeming at least briefly to assume Judge Gorsuch’s confirmation. “He’s going to keep you busy.”
Leading up to the hearings, Democrats had gotten little traction for their arguments against Judge Gorsuch. Even on Monday, the proceedings were overshadowed at times by a hearing across the Capitol, where the F.B.I. director, James B. Comey, confirmed an investigation into contacts between Russia and members of the president’s orbit.
But skeptics of Judge Gorsuch hope to amplify several concerns, turning particular attention to his case history on corporate issues and the rights of employees. Repeatedly, the example of a stranded truck driver was invoked: Judge Gorsuch had written a dissent arguing that a trucking company was permitted to fire a driver for abandoning his cargo for his own safety in subzero temperatures.
The weather was frigid, Mr. Durbin said, but “not as cold as your dissent, Judge Gorsuch.”
Ms. Feinstein said it remained to be seen whether Judge Gorsuch could acquit himself as “a reasonable mainstream conservative.” Other Democrats argued that Judge Gorsuch was handpicked by conservative groups like the Federalist Society rather than principally by Mr. Trump.
Senator Patrick J. Leahy, Democrat of Vermont, said Judge Gorsuch was “selected by interest groups.”
In their own opening remarks, Republicans often sought to accuse their counterparts of hypocrisy, suggesting they were only now awakening to anxieties over executive authority.
“Some of my colleagues seem to have rediscovered an appreciation for the need to confine each branch of the government to its constitutional sphere,” said Senator Charles E. Grassley, Republican of Iowa and the committee’s chairman.
Republicans also rejected any claim that the seat belonged to Judge Garland.
Senator Lindsey Graham, Republican of South Carolina, said that believing in a purported “great plan to get a Trump nominee on the court” required an expectation that “Trump was going to win to begin with.”
“I didn’t believe that,” said Mr. Graham, who has often criticized Mr. Trump.
Senator Ted Cruz, Republican of Texas, extended the argument considerably. This nomination carried “super-legitimacy,” he said, because “the American people played a very direct role” in the outcome by electing Mr. Trump amid a fight over an open seat.
Before the election, Mr. Cruz suggested that if Hillary Clinton won, Republicans might seek to preserve the court vacancy indefinitely.