White House chief economic adviser Gary Cohn called the CBO's analysis "meaningless" on "Fox News Sunday."
"If you're looking to the CBO for accuracy, you're looking in the wrong place," White House Press Secretary Sean Spicer told reporters last week.
The CBO's projections on President Barack Obama's Affordable Care Act were mixed, but a 2015 study by the Commonwealth Fund found they were the closest to the mark among major nonpartisan analysts.
Robert Reischauer, who directed the CBO from 1989 to 1995, told NBC News that some criticism of the agency's past projections were valid.
But, he said, CBO still has "the greatest capability of any entity to make these kinds of estimates," thanks to its experience, official role and transparent methodology.
"Would I bet my dog's life on [the CBO score]? No," Reischauer said. "But do I think it's a very solid estimate? Yes, if I had to make policy."
The report comes even as a number of moderate and conservative lawmakers have expressed skepticism the bill would lower premiums and improve coverage and it's unlikely a poor score would boost their confidence.
"I believe [the AHCA] would have adverse consequences for millions of Americans and it wouldn't deliver on our promises to reduce the cost of health insurance for Americans," Sen. Tom Cotton (R-AR), often an ally of the Trump administration, told ABC's "This Week" on Sunday.
The White House has previously accused holdovers from the Obama administration of undermining its agenda, but that argument won't hold with the CBO, whose current director, Keith Hall, was selected by Republican Congressional leaders in 2015 and previously served as an economist for President George W. Bush.
As chair of the House Budget Committee, Price lavished praise on Hall and emphasized the agency's value in crafting legislation.
"[Hall's] vast understanding of economic and labor market policy will be invaluable to the work of CBO and the important (role) it will continue to play as Congress seeks to enact policies that support a healthy and growing economy," he said in a statement after Hall's appointment to CBO.
But Price sang a less upbeat tune Friday when he was pressed on MSNBC's "Morning Joe" about Hall's role in the process, saying the CBO had a record of "woefully underperforming when it comes to evaluating health systems."
While the CBO will be the most significant analyst, outside experts on the left, right and center are already highlighting several provisions in the House plan that are likely to cause people to lose coverage.
The bill would eliminate an expansion of Medicaid that covered over 11 million people while reducing tax credits to buy insurance for many low-income Americans. Some of these cuts could be offset by a temporary fund that would provide grants to states to shore up their insurance markets, but analysts are so far skeptical they'll make up the difference.
Brookings scholars Matthew Fiedler and Loren Adler estimated at least 15 million people would lose insurance coverage under the plan. S&P Global Ratings estimated coverage loses of 6 to 10 million people.
Disagreeing with the CBO when it detracts from your arguments and highlighting its findings when it validates them is hardly new.
As critics quickly pointed out, Spicer himself cited CBO scores that corroborated attacks on Obamacare before he joined the White House. Democrats have been known to argue with the CBO as well: Obama's White House challenged the agency's 2014 assessment that an increase in the minimum wage would reduce jobs.
The current fight is notable, however, because it's occurring before the score has been made public and because Trump has repeatedly attacked the legitimacy of government data, intelligence reports and even federal judges, while at times citing fringe sources to back up claims.
Still, some of the current hand wringing over the impending score feels familiar. Reischauer ran the agency during President Bill Clinton's unsuccessful push for health care reform, when his analyses served as a wet blanket for Democratic lawmakers struggling to find a workable compromise that could provide affordable care without blowing up the deficit.
"That debate was as highly charged as this one," he said. "I look at this and see it playing out very much the same way."