The Capitol on Tuesday was full of signs that the latest iteration of the GOP health care overhaul was on life support.

In one major indication that things were not going well, Vice President Mike Pence skipped a planned appearance at a trophy ceremony for the Air Force to dash to the Hill and meet with hesitant members, none of whom emerged ready to change their minds.

Michigan Rep. Fred Upton, the former chairman of the Energy and Commerce Committee, came out as the 21st public “no” in another sign of the bill’s dwindling chances.

Those developments, coupled with Capitol Hill chatter about potential changes to the bill and dissipating optimism for a vote this week, suggest Republicans still have no viable path for fulfilling one of the party’s top campaign promises: replacing the 2010 health care law.

With 21 public “no” commitments, GOP leaders can afford no more than one more defection before they will have to rethink their strategy or give up. The bill would fail if 23 or more Republicans vote “no.”

Pence met separately with Reps. Peter Roskam of Illinois, Dave Reichert of Washington, Mike Coffman of Colorado, Daniel Webster of Florida and Charlie Dent of Pennsylvania.

Roskam, Reichert and Coffman — who had supported an earlier version of the bill — all said after meeting with Pence that they remain undecided. Roskam and Reichert voted “yes” during the Ways and Means Committee markup in March. Their hesitation shows that the latest proposal, an amendment to allow states to opt out of certain insurance regulations, is unpalatable to many moderates.

“We’re still trying to work through some issues,” Reichert said, noting that he has many questions about three issues the amendment would change: the health benefits the law requires insurers to cover, pre-existing condition protections and Medicaid expansion.

Pence did not appear to sway Webster, who has said he will continue to be a “no” unless an issue related to Florida hospital beds is addressed, or Dent, an emphatic “no” for a variety of reasons.

Later, after a regular appearance at the Senate Republican lunch, Pence met with House Speaker Paul D. Ryan, Majority Leader Kevin McCarthy and Majority Whip Steve Scalise.

Despite the evidence of trouble, GOP leaders said they remained optimistic.

“We continue to have growth on the overall vote count,” Scalise said.

Leadership is “still working through some questions” members have about the health bill, he added.

Ryan defended the legislation during a GOP conference meeting Tuesday morning, taking questions from members on how the bill would protect people with pre-existing conditions, according to Rep. Luke Messer of Indiana, chairman of the GOP’s policy committee.

Scalise downplayed the effect of members who previously supported the bill, such as Upton and Missouri Republican Billy Long, but now oppose it.

“Fred and Billy Long, we had already moved them out of the ‘yes’ column before this,” the Louisiana Republican said. “So it was expected where they were going. There are others that are trying to get there.”

McCarthy told reporters late Tuesday they were “very close” to getting the votes but declined to say how many members they needed or if the House would vote this week.

White House leaders had suggested earlier Monday the House could vote on the party’s replacement by the end of this week, but that optimism has faded among the rank and file.

“I was hopeful, but I’m not as much right now,” said New York Rep. Chris Collins, an ally of President Donald Trump and an ardent backer of the health care bill.

“They have a problem on the votes right now,” he added.

House Freedom Caucus Chairman Mark Meadows, who backs the legislation, suggested that this week was the “now or never” moment for the conference.

“If we don’t get it done this week, this bill becomes impossible to get done,” the North Carolina Republican said. “We’ve spent a lot of time trying to make this bill palatable to 216, 217 people. I don’t know that that improves with time.”

One idea being floated to make the bill more popular is adding additional money for the so-called high-risk pools in the legislation, which Republicans say would help subsidize coverage for sicker individuals who could face higher prices under the legislation.

New Jersey Rep. Tom MacArthur, the architect of the most recent amendment, confirmed there is some talk of that but said he believes the $115 billion over a decade already in the bill to help set up high-risk pools and stabilize premiums is adequate.

“At the margins, [more money] maybe helps some people get to a ‘yes,’ but I think the question is more fundamental for people: Are they comfortable with this balance if this is the best way to protect the vulnerable and not cut expenses?” he said. “If they’re not, billions here and billions there is probably not going to do a lot of good.”

Upton’s announcement that he will now oppose the bill was a significant blow to leadership’s effort to win over hesitant moderates. The Michigan Republican chaired the Energy and Commerce Committee for most of President Barack Obama’s tenure and led scores of the party’s earlier efforts to repeal and replace the health care law.

“The president said himself he wants the final version, for pre-existing folks, to be the same or better than Obamacare. That’s not the case with the House bill in it’s current state,” Upton said at the Capitol. “There’s a lot of folks that have expressed reservations as relates to the pre-existing conditions provision. There are many people in my shoes. It doesn’t fly, nor should it.”

Several other lawmakers acknowledged Upton’s vote in particular would carry great weight with fellow moderates.

“It’s important,” said Rep. Greg Walden of Oregon, who succeeded Upton as Energy and Commerce chairman and who supports the bill. “He’s a very thoughtful leader on health care and I think he represents a group of members of the conference that still have concerns about the opening of the language on pre-existing conditions.”

Dent, a co-chairman of the centrist Tuesday Group that Upton belongs to, said many members respect the Michigan lawmaker and share his concerns about protecting people with health problems.

MacArthur, also a Tuesday Group co-chairman, said he was “disappointed” to learn of Upton’s opposition.

“Fred and I have talked at length about it,” he said. “I have a lot of respect for both his understanding of things. … I just see this differently.”

Erin Mershon, Kerry Young and Andrew Siddons contributed to this report.