GOP Reps. Dave Brat of Virginia, Gary Palmer of Alabama, and Mark Sanford of South Carolina all voted against the legislation Thursday morning in the House Budget Committee. With the defections, the bill just barely passed out of the committee 19-17.

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The controversial legislation aiming to replace Obamacare had previously sailed through the House Energy and Commerce and Ways and Means committees with unanimous Republican support (and unified Democratic opposition). That was despite widespread condemnation of the legislation from industry groups representing hospitals, doctors, insurance companies, and older Americans, who warned that it would lead to widespread coverage losses and wreck medical finances for patients and the health sector alike.

Since then, an analysis by the nonpartisan Congressional Budget Office (CBO) confirmed what many had believed: that Trumpcare would lead to 24 million fewer insured Americans over the next decade, and 14 million fewer covered by next year. Premiums would also be expected to spike significantly through 2020.

The CBO score gave moderate and conservative Republicans, some of whom were already skeptical of the AHCA for a variety of reasons, cover to urge major changes to the bill. If the same percentage of the full House were to vote against the legislation as did so in the Budget Committee (assuming continued, unified Democratic opposition), Trumpcare would not pass the chamber.