But as hard as it is, leaders know they can't simply abandon their effort now.
"I hope we keep going. I don't think we can stop," said Rep. Brett Guthrie, a Republican who serves on the House's Energy and Commerce Committee told CNN last week.
White House chief economic adviser Gary Cohn sounded optimistic Monday morning when asked if he thought Republicans' plans for health care had enough votes.
"I think we do," Cohn told CBS. "This is going be a great week. We're going to get health care down to the floor of the House. We're convinced we've got the votes and we're going to keep moving on with our agenda."
Trump said Sunday the White House is pushing forward, and that the GOP plan "guarantees" coverage for Americans with pre-existing conditions.
"Pre-existing conditions are in the bill. And I mandate it. I said, 'Has to be,'" Trump said on CBS's "Face the Nation" Sunday.
Unlike the mandate under Obamacare, however, under the GOP bill insurers could charge them higher rates than others in the plan if they allow their coverage to lapse.
Republicans might seem stuck in a never ending cycle of trying to please the moderate and conservative wings of their party but pressure from the White House to deliver a legislative win for Trump is real. Also real: the repeated pledges to their constituents over the past seven years to repeal and replace Obamacare if given the chance.
There is still no official timeline to put the health care repeal and replace bill on the floor, and leadership aides are unequivocal that the bill will move only once leadership knows they have the 216 votes needed. GOP leaders continued to discuss the effort with members over the weekend -- with leaders especially focused on helping members on the fence and some outright "nos" understand what the newest amendment on the bill would do to protect those with pre-exisiting conditions -- but some question what makes this effort different from the previous failed attempts.
"I'm not terribly optimistic right now," Rep. Charlie Dent, R-Pennsylvania, told CNN's New Day. "I think we need to change the paradigm."
Last week Republicans seemed to reach a major breakthrough on health care.
A new amendment sponsored by moderate leader Rep. Tom MacArthur of New Jersey gave states the ability to opt out of more Obamacare regulations. The amendment was also enough to finally bring the conservative House Freedom Caucus on board.
But the amendment, which experts noted could drive up the cost of insurance for older Americans and those with pre-existing conditions, spooked moderates and left some -- who had been supportive of the legislation before -- scrambling to publicly voice their discontentment. All of a sudden, it was moderates in the hot seat.
It seemed that even though leadership may have gained upwards of 30 new votes from the Freedom Caucus, they were suffering significant enough losses from the other side of the party that they still couldn't bring a bill up to the floor for a vote in order to mark Trump's first 100 days in office. A CNN whip count had recorded 16 Republicans as nos. The GOP can only afford to lose 21 depending on attendance -- not a lot of room for error.
This week, leadership's focus remains trying to help those moderates get comfortable with the new MacArthur amendment. Over the weekend, House leaders, as well as Vice President Mike Pence and Health and Human Services Secretary Tom Price, spoke with members hoping to flip enough votes to move the bill forward. Leadership aides emphasize that there isn't much room to change the proposal at this point, but many deputy whips are trying to get members to keep the process in perspective.
"You remind them there is a United States Senate, and it will change things. What we send over there isn't going over there on stone tablets," said Rep. Tom Cole, R-Oklahoma.
"Going back to the drawing board would be death to repeal and replace," one aide said.
After last week, though, many moderates are frustrated with the process. Some say they see their party making the same kind of mistakes Republicans criticized Democrats for making back in 2010.
"We didn't learn anything from their mistakes," said Rep. Mark Amodei, a moderate Republican from Nevada told CNN. "We learned nothing from their mistakes."
As to promises the bill will be changed once it's in the Senate?
"Seriously, you want me to go back and tell the people in my fourth of Nevada 'the Senate will make it better?'" Amodei said. "What the hell?"
CNN's Phil Mattingly and