The president’s demands for more negotiations amounted to his fourth position in three days on the health care bill. He began the week supporting a Senate effort to overhaul the law, but when it became clear late Monday that Republicans would fall short of the votes for that measure, he abruptly declared that lawmakers should simply repeal the law and start from a “clean slate” on an effort to replace it — an approach he had previously ruled out.
Facing still more opposition for that strategy, he said on Tuesday that Republicans should “let Obamacare fail” and blame it on Democrats. But by nightfall, Mr. Trump was scheduling a lunch with Republicans at the White House, designed to pressure them to redouble their efforts to find agreement on a full-scale replacement, back where he started.
Mr. Trump usually steers clear of policy details and has grown impatient with the painstaking behind-the-scenes bargaining that has marked the health care negotiations. But he said on Wednesday that he was hopeful that the Senate would deliver a bill that he could sign.
“I think that we’re going to do O.K. — we’re going to see,” he said in an interview in the Oval Office, just after his lunch with senators in the State Dining Room.
He was blunt about the obstacles and the difficulty of the negotiations.
“It is a very narrow path winding this way,” Mr. Trump said. “You think you have it, and then you lose four on the other side because you gave” concessions to another faction of senators.
“It is a brutal process,” he added. Mr. Trump conceded that the very nature of what he had promised to do — eliminate Mr. Obama’s health care program, which serves millions of Americans — made the effort an uphill slog.
“Once you get something, it’s awfully tough to take it away,” Mr. Trump said.
There is still little evidence that returning to the negotiating table on a replacement will win over the four Republicans who have declared their opposition.
The health care bill drafted by Senator Mitch McConnell of Kentucky, the majority leader, would repeal major provisions of the Affordable Care Act, including penalties for people who go without health insurance; make deep cuts in projected Medicaid spending; and establish a new system of subsidies to help people buy private insurance.
The measure has faced resistance both from conservatives concerned that it did not go far enough in eliminating the current law and from moderates who feared it would lead to losses in insurance coverage, stingier plans and higher health costs.
Mr. Trump dispatched administration officials to Capitol Hill on Wednesday night to lobby wavering Republicans who have not yet pledged to support the measure, some of whom have publicly aired their reservations. Mr. McConnell said the goal was to get them to agree to vote next week on a procedural motion simply to open debate on the bill, but the final language of that measure had not yet been determined.
“There’s no way that I, or anybody else, could prevent members from having amendments that any 51 of us can pass and change the bill,” Mr. McConnell said. “But we cannot have a debate until we get on the bill.”
The Trump administration also offered the insurance industry an olive branch, approving the payment of a month’s worth of subsidies to insurers that help poor customers with out-of-pocket health care expenses.
The president has never been completely engaged with the health care repeal-and-replace efforts. He was largely absent from House attempts to craft a bill earlier this year, weighing in at the end when the effort appeared on the verge of collapse to issue an ultimatum.
Then, too, he initially reacted with angry resignation to the failure by House Republicans to reach consensus — “It’s enough, already,” he said after leaders scrapped a vote because they could not muster a majority for the measure — only to change course later, urging lawmakers to strike a compromise, and celebrating lavishly in the Rose Garden when they did.
He has occasionally cajoled members of Congress, primarily through his Twitter feed, but he has seemed hesitant at best. White House advisers have been divided on how involved he should be, leaving Mr. Trump to weigh in sporadically. And his impulse has been to keep members of Congress at an arm’s length, reverting to blaming and threatening them when it appears they are not bowing to his preferences — and even privately criticizing their work product, as he did when he called the House-passed bill “mean.”
“I think it’ll be very bad for them” if they don’t support the health bill, Mr. Trump said of lawmakers in the interview on Wednesday.
At lunch, Mr. Trump used a combination of humor and thinly veiled threats to pressure senators to do what he was asking.
“Look, he wants to remain a senator, doesn’t he?” Mr. Trump said of Senator Dean Heller, a Nevada Republican who was seated beside him and who has been outspoken about his concerns with the proposal. “I think the people of your state, which I know very well, I think they’re going to appreciate what you hopefully will do.”
In private, Mr. Trump was sharper, according to a person briefed on the closed-door lunch, telling Mr. Heller that if he opposed the health care effort, he would lose the Republican nomination for his Senate seat, which would bar him from seeking re-election next year. The person spoke on condition of anonymity because the discussion was private.
Mr. Trump also alluded to two Republicans, Jerry Moran of Kansas and Mike Lee of Utah, who had come out against the measure Monday night, saying he had been “surprised” because the senators were “my friends.”
“My friends — they really were and are,” he said. “They might not be very much longer, but that’s O.K.”
Senator Bill Cassidy, Republican of Louisiana, said Mr. Trump was “trying to add momentum back to a process” that had stalled.
“We’ll see,” he said. “I like to think that we walked out with a sense of momentum.”
At the White House, senators said, they discussed a proposal added to the Senate bill at the request of Senator Ted Cruz, Republican of Texas, that would allow insurers to sell policies that violate the Affordable Care Act if they also sell policies that comply with the benefit mandates and other requirements of the law.
A study by the Department of Health and Human Services, cited by Mr. Trump, said the proposal would increase enrollment and reduce premiums in the individual insurance market. But those figures are at odds with projections by insurance actuaries outside the government, who have called Mr. Cruz’s proposal unworkable and warned it would lead to higher premiums and terminations of coverage.