Senators and aides said they still hoped to reach a compromise on the legislation, with Mr. Schumer declaring after the vote that “we’re closer than we’ve been at any time over the past 48 hours to an agreement.”

“Can we overcome the remaining disagreements in the next 24 hours?” said Mr. Schumer, who estimated he met with Mr. Mnuchin for six times late Sunday evening, according to a spokesman. “Yes, we can and we should. The nation demands it.”

Later as he entered Mr. Schumer’s Capitol office, Mr. Mnuchin said the two were “this close” to a deal, holding up two fingers with scarcely an inch of distance between them.

But even as talks continued in private, Mr. McConnell laid blame for the delay at the feet of both Mr. Schumer and Speaker Nancy Pelosi of California, who returned to Washington on Saturday to partake in a leadership meeting in his office on Sunday.

Republicans and Democrats, as well as President Trump, have agreed that the plan is crucial to cushioning the economic blow of the rapidly spreading disease, which has shuttered entire industries, forced workers to stay at home and wreaked havoc in the global markets. It would send $1,200 direct payments to millions of Americans and additional jobless benefits and aid to states, and provide hundreds of billions of dollars for loans to businesses.

But as its outlines emerged on Sunday, Democrats denounced the package as a corporate giveaway that favored big business over workers and failed to ensure that bailed-out companies would not enrich themselves after receiving government aid. They were particularly incensed at the inclusion of a provision that would give the Federal Reserve access to $425 billion that could be leveraged for loans to broad groups of flailing companies, leaving Congress with little or no say in which businesses could receive assistance or how it could be used.

“In the midst of an unprecedented national crisis, Republicans can’t seriously expect us to tell people in our communities who are suffering that we shortchanged hospitals, students, workers and small businesses, but gave big corporations hundreds of billions of dollars in a secretive slush fund,” said Senator Patty Murray, Democrat of Washington, who has largely negotiated over the phone in part as a precaution.